Nigeria's state oil company withheld 3.2 trillion naira ($16 billion) in revenues from the federal government in 2014, the auditor-general said on Monday, the same year that the central bank governor was suspended after making a similar assessment.
Constitutionally, the Nigerian National Petroleum Company (NNPC) must hand over all oil revenue - which makes up about 70 percent of total income - and money is then paid back based on a budget approved by parliament.
Samuel Ukura, who presented his findings in a report to lawmakers at the national assembly, said other government ministries and agencies had also failed to remit funds, taking the total not passed on to 3.3 trillion naira for 2014.
No one at the NNPC could immediately be reached to comment or provide details of the amount remitted that year. According to the latest figures on OPEC's website, Nigeria's oil exports are worth about $77 billion a year.
Development in Nigeria, Africa's biggest oil producer and largest economy, has been stunted by decades of corruption and mismanagement. President Muhammadu Buhari took office last year on an anti-corruption ticket.
Ukura's report stated that it was based on an "examination of NNPC mandates to CBN (Central Bank of Nigeria) on Domestic Crude Oil Sales and Reconciliation Statement of Technical Sub-committee of Federation Account Allocation Committee (FAAC) meeting held in January 2014".
"Amount not remitted to FAAC was N3,234,577,666,791.35," the auditor-general said in his report.
In 2014, the then central bank governor, Lamido Sanusi, was suspended after accusing the NNPC of failing to pay $20 billion into government accounts between January 2012 and July 2013.