Najib, who was sentenced to 12 years in prison after being convicted in a case linked to the 1MDB scandal, had applied for clemency previously but the pardons board, which is chaired by Malaysia's king, opted last week to reduce his sentence.
Najib's lawyer Tan Sri Muhammad Shafee Abdullah said a new request was being considered as his client had not received a fair trial. Najib has consistently denied wrongdoing.
The lawyer also raised questions over the pardons process led by Yang di-Pertuan Agong Al-Sultan Abdullah Ri’ayatuddin Al-Mustafa Billah Shah, who ended his five-year reign as king on Jan. 30, shortly after issuing the sentence reduction for Najib.
"I don't think the pardons board operated the way the constitution dictates it operates," Shafee said.
