Former premier Mahathir Mohamad's son quit the ruling party today after his father called for mass resignations to force the ouster of Prime Minister Abdullah Ahmad Badawi.

mahathir heart institute ijn 160507 mokhzani Businessman Mokhzani Mahathir warned Umno was heading for "annihilation" unless Abdullah stepped down to take responsibility for disastrous March election results.

But he denied there was a rift in the family after his younger brother Mukhriz, a senior member of Umno's influential youth wing, declined to follow his father's example and resign from the party.

"There's no conflict from within the family. The goals and the agenda are the same," Mokhzani told AFP .

"My brother has decided to stay because there must be people who remain within the party to fight from within. I think my brother is in a position to make a difference within the party and I hope he does," he said.

Mokhzani, one of Malaysia's top businessmen, at one time served as the treasurer of Umno's youth wing, but no longer holds high office.

Not everything is 'fine and dandy'

Mahathir quit the party on Monday and said he would not rejoin until Abdullah had left, causing a panic in the ranks as top members said they feared an exodus would unseat the government and trigger fresh elections.

His wife, Siti Hasmah, has also given up her Umno membership on the same day.

But the following day Umno lawmakers pledged allegiance to Abdullah and few resignations have ensued.

"Nobody dares voice their grievances or concerns or make public their views, Everyone's trying to say everything's fine and dandy which it isn't," Mokhzani said.

"If the party continues on the path it's going on today, I think the next general election will see its total annihilation," he added.

The crisis has triggered an emergency meeting of Umno's decision-making supreme council which will be held later tonight.

The ruling coalition lost five states and a third of parliamentary seats in March 8 polls, but Abdullah has repeatedly refused to stand down despite calls from Mahathir who has become his leading critic.

Mahathir picked Abdullah as his successor when he stepped down in 2003 after 22 years in power, but the two fell out shortly after and Mahathir accuses him of corruption, mismanagement and nepotism.