President Muhammadu Buhari has ordered ministries to use only approved government bank accounts to make payments, the vice president’s office said on Sunday as part of drive to improve transparency and clamp down on corruption.

Buhari, who on assuming office in May promised to fight endemic graft in Africa’s biggest economy, said he believes officials have stolen around $150 billion from the public purse over the past decade.

Under the new system, all receipts due to the government or any of its agencies must be paid into accounts maintained by the central bank unless specific permission has been granted not to do so.

“President Muhammadu Buhari has ordered each and every federal government ministry, department or agency to start paying into a Treasury Single Account (TSA) for all government revenues, incomes and other receipts,” said Laolu Akande, a spokesman for Vice President Yemi Osinbajo.

“This measure is specifically to promote transparency,” he said, adding that the TSA would be linked to other government bank accounts.

Akande also said that the new system would end the use of “several fragmented accounts for government revenues,” which he said had led to “the loss or leakages of legitimate income meant for the federation account.”

The effectiveness of this change in public accounting remains to be seen since corruption and mismanagement of public funds have been entrenched in Nigeria’s political system for decades.

Last month, Buhari said his administration would trace and recover what he called “mind-boggling” sums of money stolen from the oil sector, which provides about 70 percent of revenues of the government in Africa’s biggest crude producer.

•Photo shows President Buhari.