The Senate has queried the Budget Office of Federation over alleged excess payment of N28.8bn to some ministries, departments and agencies of government.
The Senate Public Accounts Committee, relying on a 2016 audit report, said the alleged infraction was committed in 2015.
The committee, chaired by Senator Matthew Urhoghide, is probing the spendings of government agencies using the audit report.
The query reads: "There was no evidence to show that these advances were recovered from the subsequent payments made to these MDAs, resulting in excess releases to the benefiting MDAs, above their appropriated amounts.
"Furthermore, there was no evidence of any supplementary budgetary allocation from the National Assembly.
"The Director-General was requested to recover these advances from the benefiting MDAs from subsequent payments due to them or show evidence of supplementary approval from the National Assembly for the sum of N28,880,533,107.00 released as advances. Evidence of compliance should be furnished for verification."
But the Budget Office, in a written response as captured in the audit report, said, "The details of the MDAs under reference have not been provided to enable us respond appropriately."