Prime Minister Dr Mahathir Mohamad has confirmed that Bank Negara governor Muhammad Ibrahim has resigned.

"We have not decided on his successor because we need to have the approval of the (Yang di-Pertuan) Agong before we can (make the announcement)," he said.

Mahathir was speaking to reporters in Putrajaya this afternoon after chairing the weekly cabinet meeting.

Muhammad was appointed governor on May 1, 2016, replacing Zeti Akhtar Aziz.

His resignation comes in the wake of reports that he was under pressure to quit due to being perceived as former prime minister Najib Abdul Razak's man.

Mahathir said he had received Muhammad's resignation letter and that it did not contain specific reasons for quitting.

"He didn't (state) any concrete reasons. He expressed a desire to resign," said the prime minister. 

On when he will nominate Muhammad's successor to the Yang di-Pertuan Agong, Mahathir replied: "As soon as possible."

A Universiti Malaya trained accountant, Muhammad joined Bank Negara in 1984 and was appointed deputy governor in 2010. 

He replaced governor Zeti Akhtar Aziz, who had already served 16 years under three prime ministers, in May 2016.

Muhammad's tenure was relatively uneventful until it was revealed that Bank Negara had acquired land from the federal government. 

Proceeds from the sale went to finance a portion of 1MDB's debt. Bank Negara had maintained that the transaction was aboveboard and done at arm's length. 

The term of Muhammad, 62, is the shortest ever for a Bank Negara governor.