Malaysia's attorney general on Friday temporarily blocked the transfer of former Prime Minister Najib Razak from prison to house arrest to serve the remainder of his graft sentence at home, saying more legal clarification was needed.

The last-minute intervention came after local media reported that Najib had left the prison, after his political party paid a 50 million ringgit ($12. 3 million) fine required under the terms of a royal pardon allowing house arrest.

The attorney general's office said in a statement that Najib would remain in prison until the legal matters were resolved.