<?xml version="1.0" encoding="utf-8"?>
<!--Generated by DataTracks Rainbow version 3.0 for Toppan Merrill on 31-March-2022 [12:04:30] {AM}-->
<linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
<roleRef xlink:type="simple" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#ConsolidatedStatementOfComprehensiveIncome" roleURI="http://www.orange.be/role/ConsolidatedStatementOfComprehensiveIncome" />
<roleRef xlink:type="simple" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#ConsolidatedStatementOfFinancialPosition" roleURI="http://www.orange.be/role/ConsolidatedStatementOfFinancialPosition" />
<roleRef xlink:type="simple" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#ConsolidatedCashFlowStatement" roleURI="http://www.orange.be/role/ConsolidatedCashFlowStatement" />
<roleRef xlink:type="simple" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#ConsolidatedStatementOfChangesInEquity" roleURI="http://www.orange.be/role/ConsolidatedStatementOfChangesInEquity" />
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfComprehensiveIncome">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfTelecommunicationServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfTelecommunicationServices" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_RevenueFromConvergentServices" xlink:label="loc_OBEL_RevenueFromConvergentServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_RevenueFromRenderingOfTelecommunicationServices" xlink:to="loc_OBEL_RevenueFromConvergentServices" use="optional" order="1" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_RevenueFromRenderingOfTelecommunicationServices" xlink:to="loc_ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" use="optional" order="2" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_RevenueFromRenderingOfTelecommunicationServices" xlink:to="loc_ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" use="optional" order="3" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfInternetAndDataServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfInternetAndDataServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_RevenueFromRenderingOfTelecommunicationServices" xlink:to="loc_ifrs-full_RevenueFromRenderingOfInternetAndDataServices" use="optional" order="4" weight="1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfComprehensiveIncome">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncome" xlink:label="loc_ifrs-full_ComprehensiveIncome" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss" xlink:label="loc_ifrs-full_ProfitLoss" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ComprehensiveIncome" xlink:to="loc_ifrs-full_ProfitLoss" use="optional" order="5" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ComprehensiveIncome" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" use="optional" order="6" weight="1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfComprehensiveIncome">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss" xlink:label="loc_ifrs-full_ProfitLoss" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxExpenseContinuingOperations" xlink:label="loc_ifrs-full_IncomeTaxExpenseContinuingOperations" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLoss" xlink:to="loc_ifrs-full_IncomeTaxExpenseContinuingOperations" use="optional" order="7" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossBeforeTax" xlink:label="loc_ifrs-full_ProfitLossBeforeTax" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLoss" xlink:to="loc_ifrs-full_ProfitLossBeforeTax" use="optional" order="8" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLossFromOperatingActivities" xlink:label="loc_ifrs-full_ProfitLossFromOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossBeforeTax" xlink:to="loc_ifrs-full_ProfitLossFromOperatingActivities" use="optional" order="9" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Revenue" xlink:label="loc_ifrs-full_Revenue" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_Revenue" use="optional" order="10" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_RevenueFromConvergentServices" xlink:label="loc_OBEL_RevenueFromConvergentServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_OBEL_RevenueFromConvergentServices" use="optional" order="11" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfInterconnectionServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfInterconnectionServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromRenderingOfInterconnectionServices" use="optional" order="12" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfOtherTelecommunicationServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfOtherTelecommunicationServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromRenderingOfOtherTelecommunicationServices" use="optional" order="13" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromRenderingOfMobileTelephoneServices" use="optional" order="14" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromRenderingOfLandLineTelephoneServices" use="optional" order="15" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromRenderingOfInternetAndDataServices" xlink:label="loc_ifrs-full_RevenueFromRenderingOfInternetAndDataServices" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromRenderingOfInternetAndDataServices" use="optional" order="16" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RevenueFromSaleOfTelecommunicationEquipment" xlink:label="loc_ifrs-full_RevenueFromSaleOfTelecommunicationEquipment" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Revenue" xlink:to="loc_ifrs-full_RevenueFromSaleOfTelecommunicationEquipment" use="optional" order="17" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_DirectCosts" xlink:label="loc_OBEL_DirectCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_OBEL_DirectCosts" use="optional" order="18" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CostOfSales" xlink:label="loc_ifrs-full_CostOfSales" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_DirectCosts" xlink:to="loc_ifrs-full_CostOfSales" use="optional" order="19" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_OtherDirectCosts" xlink:label="loc_OBEL_OtherDirectCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_DirectCosts" xlink:to="loc_OBEL_OtherDirectCosts" use="optional" order="20" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ImpairmentLossRecognisedInProfitOrLossTradeReceivables" xlink:label="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossTradeReceivables" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_DirectCosts" xlink:to="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossTradeReceivables" use="optional" order="21" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_IndirectCosts" xlink:label="loc_OBEL_IndirectCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_OBEL_IndirectCosts" use="optional" order="22" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_SalesAndMarketingExpense" xlink:label="loc_ifrs-full_SalesAndMarketingExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_SalesAndMarketingExpense" use="optional" order="23" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_OtherInformationTechnologyAndNetworkExpenses" xlink:label="loc_OBEL_OtherInformationTechnologyAndNetworkExpenses" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_OBEL_OtherInformationTechnologyAndNetworkExpenses" use="optional" order="24" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PropertyServiceChargeExpense" xlink:label="loc_ifrs-full_PropertyServiceChargeExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_PropertyServiceChargeExpense" use="optional" order="25" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_GeneralAndAdministrativeExpense" xlink:label="loc_ifrs-full_GeneralAndAdministrativeExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_GeneralAndAdministrativeExpense" use="optional" order="26" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_MiscellaneousOtherOperatingIncome" xlink:label="loc_ifrs-full_MiscellaneousOtherOperatingIncome" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_MiscellaneousOtherOperatingIncome" use="optional" order="27" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_MiscellaneousOtherOperatingExpense" xlink:label="loc_ifrs-full_MiscellaneousOtherOperatingExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_MiscellaneousOtherOperatingExpense" use="optional" order="28" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DepreciationRightofuseAssets" xlink:label="loc_ifrs-full_DepreciationRightofuseAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_IndirectCosts" xlink:to="loc_ifrs-full_DepreciationRightofuseAssets" use="optional" order="29" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ExpenseOfRestructuringActivities" xlink:label="loc_ifrs-full_ExpenseOfRestructuringActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_ExpenseOfRestructuringActivities" use="optional" order="30" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DepreciationAndAmortisationExpense" xlink:label="loc_ifrs-full_DepreciationAndAmortisationExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_DepreciationAndAmortisationExpense" use="optional" order="31" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ImpairmentLossRecognisedInProfitOrLoss" xlink:label="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLoss" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLoss" use="optional" order="32" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod" xlink:label="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod" use="optional" order="33" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ImpairmentLossRecognisedInProfitOrLossGoodwill" xlink:label="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossGoodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_ImpairmentLossRecognisedInProfitOrLossGoodwill" use="optional" order="34" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EmployeeBenefitsExpense" xlink:label="loc_ifrs-full_EmployeeBenefitsExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossFromOperatingActivities" xlink:to="loc_ifrs-full_EmployeeBenefitsExpense" use="optional" order="35" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_FinanceIncomeCost" xlink:label="loc_ifrs-full_FinanceIncomeCost" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ProfitLossBeforeTax" xlink:to="loc_ifrs-full_FinanceIncomeCost" use="optional" order="36" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_FinanceCosts" xlink:label="loc_ifrs-full_FinanceCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_FinanceIncomeCost" xlink:to="loc_ifrs-full_FinanceCosts" use="optional" order="37" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_FinanceIncome" xlink:label="loc_ifrs-full_FinanceIncome" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_FinanceIncomeCost" xlink:to="loc_ifrs-full_FinanceIncome" use="optional" order="38" weight="1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedCashFlowStatement">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncreaseDecreaseInCashAndCashEquivalents" xlink:label="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:label="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents" xlink:to="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" use="optional" order="1" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" xlink:label="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" use="optional" order="2" weight="-1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" xlink:label="loc_OBEL_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="loc_OBEL_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" use="optional" order="3" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities" xlink:label="loc_ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="loc_ifrs-full_CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities" use="optional" order="4" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInDecreaseIncreaseInShorttermDepositsAndInvestments" xlink:label="loc_ifrs-full_CashFlowsFromUsedInDecreaseIncreaseInShorttermDepositsAndInvestments" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="loc_ifrs-full_CashFlowsFromUsedInDecreaseIncreaseInShorttermDepositsAndInvestments" use="optional" order="5" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:label="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents" xlink:to="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" use="optional" order="6" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RepaymentsOfNoncurrentBorrowings" xlink:label="loc_ifrs-full_RepaymentsOfNoncurrentBorrowings" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_ifrs-full_RepaymentsOfNoncurrentBorrowings" use="optional" order="7" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" xlink:label="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" use="optional" order="8" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInIncreaseDecreaseInCurrentBorrowings" xlink:label="loc_ifrs-full_CashFlowsFromUsedInIncreaseDecreaseInCurrentBorrowings" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_ifrs-full_CashFlowsFromUsedInIncreaseDecreaseInCurrentBorrowings" use="optional" order="9" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsToAcquireOrRedeemEntitysShares" xlink:label="loc_ifrs-full_PaymentsToAcquireOrRedeemEntitysShares" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_ifrs-full_PaymentsToAcquireOrRedeemEntitysShares" use="optional" order="10" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities" xlink:label="loc_ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="loc_ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities" use="optional" order="11" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalents" xlink:to="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" use="optional" order="12" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss" xlink:label="loc_ifrs-full_ProfitLoss" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_ProfitLoss" use="optional" order="13" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForIncreaseDecreaseInOtherOperatingPayables" xlink:label="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInOtherOperatingPayables" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInOtherOperatingPayables" use="optional" order="14" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDepreciationAndAmortisationExpense" xlink:label="loc_ifrs-full_AdjustmentsForDepreciationAndAmortisationExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForDepreciationAndAmortisationExpense" use="optional" order="15" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_AdjustmentsForDepreciationAndAmortisationExpenseRightOfUseAssets" xlink:label="loc_OBEL_AdjustmentsForDepreciationAndAmortisationExpenseRightOfUseAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_OBEL_AdjustmentsForDepreciationAndAmortisationExpenseRightOfUseAssets" use="optional" order="16" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss" xlink:label="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss" use="optional" order="17" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets" xlink:label="loc_ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets" use="optional" order="18" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForProvisions" xlink:label="loc_ifrs-full_AdjustmentsForProvisions" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForProvisions" use="optional" order="19" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForUndistributedProfitsOfAssociates" xlink:label="loc_ifrs-full_AdjustmentsForUndistributedProfitsOfAssociates" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForUndistributedProfitsOfAssociates" use="optional" order="20" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForIncomeTaxExpense" xlink:label="loc_ifrs-full_AdjustmentsForIncomeTaxExpense" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForIncomeTaxExpense" use="optional" order="21" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForFinanceCosts" xlink:label="loc_ifrs-full_AdjustmentsForFinanceCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForFinanceCosts" use="optional" order="22" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_AdjustmentsForOperationalForeignExchangeAndDerivativesLossesGainsNet" xlink:label="loc_OBEL_AdjustmentsForOperationalForeignExchangeAndDerivativesLossesGainsNet" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_OBEL_AdjustmentsForOperationalForeignExchangeAndDerivativesLossesGainsNet" use="optional" order="23" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForSharebasedPayments" xlink:label="loc_ifrs-full_AdjustmentsForSharebasedPayments" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForSharebasedPayments" use="optional" order="24" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossTradeAndOtherReceivables" xlink:label="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossTradeAndOtherReceivables" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossTradeAndOtherReceivables" use="optional" order="25" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForImpairmentLossRecognisedInProfitOrLossGoodwill" xlink:label="loc_ifrs-full_AdjustmentsForImpairmentLossRecognisedInProfitOrLossGoodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForImpairmentLossRecognisedInProfitOrLossGoodwill" use="optional" order="26" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDecreaseIncreaseInInventories" xlink:label="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInInventories" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInInventories" use="optional" order="27" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable" xlink:label="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForDecreaseIncreaseInTradeAccountReceivable" use="optional" order="28" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable" xlink:label="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_AdjustmentsForIncreaseDecreaseInTradeAccountPayable" use="optional" order="29" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_AdjustmentsForIncreaseDecreaseInCustomerContractAssets" xlink:label="loc_OBEL_AdjustmentsForIncreaseDecreaseInCustomerContractAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_OBEL_AdjustmentsForIncreaseDecreaseInCustomerContractAssets" use="optional" order="30" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_AdjustmentsForIncreaseDecreaseInCustomerContractLiabilities" xlink:label="loc_OBEL_AdjustmentsForIncreaseDecreaseInCustomerContractLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_OBEL_AdjustmentsForIncreaseDecreaseInCustomerContractLiabilities" use="optional" order="31" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_AdjustmentsForIncreaseDecreaseInOtherAssetsAndDecreaseIncreaseInOtherLiabilities" xlink:label="loc_OBEL_AdjustmentsForIncreaseDecreaseInOtherAssetsAndDecreaseIncreaseInOtherLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_OBEL_AdjustmentsForIncreaseDecreaseInOtherAssetsAndDecreaseIncreaseInOtherLiabilities" use="optional" order="32" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherInflowsOutflowsOfCashClassifiedAsOperatingActivities" xlink:label="loc_ifrs-full_OtherInflowsOutflowsOfCashClassifiedAsOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_OtherInflowsOutflowsOfCashClassifiedAsOperatingActivities" use="optional" order="33" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InterestPaidClassifiedAsOperatingActivities" xlink:label="loc_ifrs-full_InterestPaidClassifiedAsOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_InterestPaidClassifiedAsOperatingActivities" use="optional" order="34" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IncomeTaxesPaidClassifiedAsOperatingActivities" xlink:label="loc_ifrs-full_IncomeTaxesPaidClassifiedAsOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="loc_ifrs-full_IncomeTaxesPaidClassifiedAsOperatingActivities" use="optional" order="35" weight="-1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedCashFlowStatement">
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_OrganicCashFlow" xlink:label="loc_OBEL_OrganicCashFlow" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_OrganicCashFlow" xlink:to="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" use="optional" order="36" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" xlink:label="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_OrganicCashFlow" xlink:to="loc_ifrs-full_PurchaseOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets" use="optional" order="60" weight="-1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" xlink:label="loc_OBEL_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_OrganicCashFlow" xlink:to="loc_OBEL_IncreaseDecreaseInPayablesRelatedToPropertyPlantAndEquipmentAndIntangibleAssetsOtherThanGoodwill" use="optional" order="61" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" xlink:label="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_OBEL_OrganicCashFlow" xlink:to="loc_ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities" use="optional" order="62" weight="-1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfChangesInEquity">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ComprehensiveIncome" xlink:label="loc_ifrs-full_ComprehensiveIncome" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ProfitLoss" xlink:label="loc_ifrs-full_ProfitLoss" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ComprehensiveIncome" xlink:to="loc_ifrs-full_ProfitLoss" use="optional" order="1" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_ComprehensiveIncome" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxCashFlowHedges" use="optional" order="2" weight="1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfFinancialPosition">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Assets" xlink:label="loc_ifrs-full_Assets" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets" xlink:label="loc_ifrs-full_NoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Assets" xlink:to="loc_ifrs-full_NoncurrentAssets" use="optional" order="1" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Goodwill" xlink:label="loc_ifrs-full_Goodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_Goodwill" use="optional" order="2" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IntangibleAssetsOtherThanGoodwill" xlink:label="loc_ifrs-full_IntangibleAssetsOtherThanGoodwill" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_IntangibleAssetsOtherThanGoodwill" use="optional" order="3" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PropertyPlantAndEquipment" xlink:label="loc_ifrs-full_PropertyPlantAndEquipment" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_PropertyPlantAndEquipment" use="optional" order="4" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RightofuseAssetsThatDoNotMeetDefinitionOfInvestmentProperty" xlink:label="loc_ifrs-full_RightofuseAssetsThatDoNotMeetDefinitionOfInvestmentProperty" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_RightofuseAssetsThatDoNotMeetDefinitionOfInvestmentProperty" use="optional" order="5" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InvestmentAccountedForUsingEquityMethod" xlink:label="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod" use="optional" order="6" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentFinancialAssets" xlink:label="loc_ifrs-full_OtherNoncurrentFinancialAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_OtherNoncurrentFinancialAssets" use="optional" order="7" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentAssets" xlink:label="loc_ifrs-full_OtherNoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_OtherNoncurrentAssets" use="optional" order="8" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxAssets" xlink:label="loc_ifrs-full_DeferredTaxAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentAssets" xlink:to="loc_ifrs-full_DeferredTaxAssets" use="optional" order="9" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentAssets" xlink:label="loc_ifrs-full_CurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Assets" xlink:to="loc_ifrs-full_CurrentAssets" use="optional" order="10" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Inventories" xlink:label="loc_ifrs-full_Inventories" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_Inventories" use="optional" order="11" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTradeReceivables" xlink:label="loc_ifrs-full_CurrentTradeReceivables" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CurrentTradeReceivables" use="optional" order="12" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_ContractAssetsAndAssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomersCurrent" xlink:label="loc_OBEL_ContractAssetsAndAssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomersCurrent" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_OBEL_ContractAssetsAndAssetsRecognisedFromCostsToObtainOrFulfilContractsWithCustomersCurrent" use="optional" order="13" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherCurrentFinancialAssets" xlink:label="loc_ifrs-full_OtherCurrentFinancialAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_OtherCurrentFinancialAssets" use="optional" order="14" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentDerivativeFinancialAssets" xlink:label="loc_ifrs-full_CurrentDerivativeFinancialAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CurrentDerivativeFinancialAssets" use="optional" order="15" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherCurrentAssets" xlink:label="loc_ifrs-full_OtherCurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_OtherCurrentAssets" use="optional" order="16" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentReceivablesFromTaxesOtherThanIncomeTax" xlink:label="loc_ifrs-full_CurrentReceivablesFromTaxesOtherThanIncomeTax" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CurrentReceivablesFromTaxesOtherThanIncomeTax" use="optional" order="17" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxAssetsCurrent" xlink:label="loc_ifrs-full_CurrentTaxAssetsCurrent" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CurrentTaxAssetsCurrent" use="optional" order="18" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentPrepaidExpenses" xlink:label="loc_ifrs-full_CurrentPrepaidExpenses" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CurrentPrepaidExpenses" use="optional" order="19" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CashAndCashEquivalents" xlink:label="loc_ifrs-full_CashAndCashEquivalents" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentAssets" xlink:to="loc_ifrs-full_CashAndCashEquivalents" use="optional" order="20" weight="1" />
</calculationLink>
<calculationLink xlink:type="extended" xlink:role="http://www.orange.be/role/ConsolidatedStatementOfFinancialPosition">
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityAndLiabilities" xlink:label="loc_ifrs-full_EquityAndLiabilities" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Equity" xlink:label="loc_ifrs-full_Equity" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAndLiabilities" xlink:to="loc_ifrs-full_Equity" use="optional" order="21" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_EquityAttributableToOwnersOfParent" xlink:label="loc_ifrs-full_EquityAttributableToOwnersOfParent" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_Equity" xlink:to="loc_ifrs-full_EquityAttributableToOwnersOfParent" use="optional" order="22" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IssuedCapital" xlink:label="loc_ifrs-full_IssuedCapital" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAttributableToOwnersOfParent" xlink:to="loc_ifrs-full_IssuedCapital" use="optional" order="23" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherReserves" xlink:label="loc_ifrs-full_OtherReserves" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAttributableToOwnersOfParent" xlink:to="loc_ifrs-full_OtherReserves" use="optional" order="24" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RetainedEarnings" xlink:label="loc_ifrs-full_RetainedEarnings" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAttributableToOwnersOfParent" xlink:to="loc_ifrs-full_RetainedEarnings" use="optional" order="25" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_TreasuryShares" xlink:label="loc_ifrs-full_TreasuryShares" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAttributableToOwnersOfParent" xlink:to="loc_ifrs-full_TreasuryShares" use="optional" order="26" weight="-1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLiabilities" xlink:label="loc_ifrs-full_NoncurrentLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAndLiabilities" xlink:to="loc_ifrs-full_NoncurrentLiabilities" use="optional" order="27" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LongtermBorrowings" xlink:label="loc_ifrs-full_LongtermBorrowings" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_LongtermBorrowings" use="optional" order="28" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLeaseLiabilities" xlink:label="loc_ifrs-full_NoncurrentLeaseLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_NoncurrentLeaseLiabilities" use="optional" order="29" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentProvisionsForEmployeeBenefits" xlink:label="loc_ifrs-full_NoncurrentProvisionsForEmployeeBenefits" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_NoncurrentProvisionsForEmployeeBenefits" use="optional" order="30" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LongtermProvisionForDecommissioningRestorationAndRehabilitationCosts" xlink:label="loc_ifrs-full_LongtermProvisionForDecommissioningRestorationAndRehabilitationCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_LongtermProvisionForDecommissioningRestorationAndRehabilitationCosts" use="optional" order="31" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentLiabilities" xlink:label="loc_ifrs-full_OtherNoncurrentLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_OtherNoncurrentLiabilities" use="optional" order="32" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxLiabilities" xlink:label="loc_ifrs-full_DeferredTaxLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_NoncurrentLiabilities" xlink:to="loc_ifrs-full_DeferredTaxLiabilities" use="optional" order="33" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentLiabilities" xlink:label="loc_ifrs-full_CurrentLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_EquityAndLiabilities" xlink:to="loc_ifrs-full_CurrentLiabilities" use="optional" order="34" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentPayablesForPurchaseOfNoncurrentAssets" xlink:label="loc_ifrs-full_CurrentPayablesForPurchaseOfNoncurrentAssets" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentPayablesForPurchaseOfNoncurrentAssets" use="optional" order="35" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers" xlink:label="loc_ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_TradeAndOtherCurrentPayablesToTradeSuppliers" use="optional" order="36" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings" xlink:label="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentBorrowingsAndCurrentPortionOfNoncurrentBorrowings" use="optional" order="37" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentLeaseLiabilities" xlink:label="loc_ifrs-full_CurrentLeaseLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentLeaseLiabilities" use="optional" order="38" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentDerivativeFinancialLiabilities" xlink:label="loc_ifrs-full_CurrentDerivativeFinancialLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentDerivativeFinancialLiabilities" use="optional" order="39" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentProvisionsForEmployeeBenefits" xlink:label="loc_ifrs-full_CurrentProvisionsForEmployeeBenefits" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentProvisionsForEmployeeBenefits" use="optional" order="40" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ShorttermProvisionForDecommissioningRestorationAndRehabilitationCosts" xlink:label="loc_ifrs-full_ShorttermProvisionForDecommissioningRestorationAndRehabilitationCosts" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_ShorttermProvisionForDecommissioningRestorationAndRehabilitationCosts" use="optional" order="41" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ShorttermRestructuringProvision" xlink:label="loc_ifrs-full_ShorttermRestructuringProvision" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_ShorttermRestructuringProvision" use="optional" order="42" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherCurrentLiabilities" xlink:label="loc_ifrs-full_OtherCurrentLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_OtherCurrentLiabilities" use="optional" order="43" weight="1" />
<loc xlink:type="locator" xlink:href="5493007JS0ZHJVBUWP18-2021-12-31.xsd#obel_CurrentPayablesOnTaxesOtherThanIncomeTax" xlink:label="loc_OBEL_CurrentPayablesOnTaxesOtherThanIncomeTax" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_OBEL_CurrentPayablesOnTaxesOtherThanIncomeTax" use="optional" order="44" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxLiabilitiesCurrent" xlink:label="loc_ifrs-full_CurrentTaxLiabilitiesCurrent" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentTaxLiabilitiesCurrent" use="optional" order="45" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentContractLiabilities" xlink:label="loc_ifrs-full_CurrentContractLiabilities" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_CurrentContractLiabilities" use="optional" order="46" weight="1" />
<loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredIncomeClassifiedAsCurrent" xlink:label="loc_ifrs-full_DeferredIncomeClassifiedAsCurrent" />
<calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ifrs-full_CurrentLiabilities" xlink:to="loc_ifrs-full_DeferredIncomeClassifiedAsCurrent" use="optional" order="47" weight="1" />
</calculationLink>
</linkbase>