Advertisement In a tweet on Thursday, the NNPC said applicants must be “reputable audit, accounting, financial consulting and tax advisory firms with proven record and vast experience in the oil and gas industry in Nigeria or similar experience for foreign companies”. JUST IN:@NNPCgroup Invites Bids for the Selection of Audit , Accounting & Tax Advisory Services. Advertisement The duration of the call off term contract shall be for a period of three years. However, the contract will lapse on December 31, 2023 irrespective of the effective date of such engagement. Advertisement Interested companies must submit expressions of interest (EOIs) via the NNPC/Nipex tender portal.