Embezzlement and bribery with government money are among the charges that Malaysia is looking to bring against former leader Najib Razak following a probe into funds allegedly looted from the state-run fund 1MDB, Prime Minister Mahathir Mohamad has said.

Mahathir said in a Tuesday interview that Malaysian investigators already "have an almost perfect case" against the principal suspects who had defrauded 1Malaysia Development Berhad (1MDB) and misappropriated billions of dollars in public funds.

He also described Najib, who founded 1MDB in 2009, as playing a central role.