Umno man Khairuddin Abu Hassan's sudden support for former opposition leader Anwar Ibrahim may have been induced by a life-changing experience while in police custody, said Anwar's wife Dr Wan Azizah Wan Ismail.

"When he went inside, he must have repented after being arrested and getting dengue.

"We have maintained from the beginning that Anwar is innocent and should be freed," Wan Azizah told reporters at the Parliament lobby today.

Khairuddin on Sunday made a surprise statement calling for Anwar's release so that there is a strong opposition against the current government.

This came weeks after Khairuddin himself was released from police custody on bail, after being charged with sabotaging the Malaysian economy over his many reports lodged against 1MDB.

The former Batu Kawan Umno deputy chief was arrested on Sept 18, and was infected with dengue fever a week later while in the Dang Wangi district police headquarters lockup.

Anwar was jailed in February after the Federal Court upheld a Court of Appeal ruling that the PKR de facto leader was guilty of sodomy.

Anwar and his supporters claim the charge and his detention are politically motivated.