Datuk Seri Nazir Razak will end nearly three decades at Malaysian banking giant CIMB on Dec 31, the latest in a string of top guns to exit government-linked companies since the Pakatan Harapan coalition took power in May.

A statement by CIMB, South-east Asia's fifth largest lender and Malaysia's second largest, yesterday said Mr Nazir, the younger brother of former premier Najib Razak, will relinquish all positions including group chairman, at the end of the year.

"It was always going to be hard to find the perfect moment... to leave CIMB - not too soon, not too late - but always with the firm's best interest in mind," Mr Nazir said. He said "my CIMB mission" has been completed with the bank's four-year recalibration plan to turn it into a universal bank for the region.

On Instagram, he added that "I am 52 years young. It is time for me to commit fully to my next mission on the Asean stage", but did not elaborate on future plans after 29 years at the bank.

Mr Nazir was CIMB's group CEO for 15 years before moving up to become chairman in 2014. Under his leadership, CIMB's value hit RM58 billion (S$19 billion) at end-June. It was listed in 2003 with a market capitalisation of RM1.5 billion.

The Straits Times understands that Mr Nazir was among the earliest names listed by the new government to be forced out of office.