KUALA LUMPUR • Malaysia's for- mer premier Mahathir Mohamad has resigned as chairman of national carmaker Proton Holdings with effect from Wednesday, amid a bitter spat with Prime Minister Najib Razak.

The 90-year-old has also stepped down from his posts as Chancellor of Universiti Teknologi Petronas and adviser to the Langkawi Development Authority and the Tioman Island Development Authority, his office announced yesterday.

Proton Holdings, in a statement, said it respected his wishes.

"We would like to express our gratitude and recognise Dr Maha- thir's role as the creator of the national car company," Proton said.

The firm, which is owned by DRB-Hicom, also said Dr Mahathir has resigned as chairman of Group Lotus, a wholly owned subsidiary of Proton.

Tun Dr Mahathir is still honorary president of Perdana Leadership Foundation, a non-profit institution that disseminates information on Malaysia's former prime ministers.

Earlier last month, Dr Mahathir was sacked as adviser of state- owned energy firm Petronas - Malaysia's only Fortune 500 company - after launching a "Citizen's Declaration" together with opposition leaders to try to remove Mr Najib, citing his poor leadership and alleged wrongdoing in managing indebted state fund 1Malaysia Development Berhad.

Trinna Leong