The son of former Malaysian premier Mahathir Mohamad on Friday asked Prime Minister Abdullah Ahmad Badawi to resign following the ruling coalition's election debacle at the weekend.

'I'm asking him to resign,' Mukhriz Mahathir, a senior executive member of the United Malays National Organisation (UNMO) and who commands factional support within the party, told Reuters by telephone, adding that he had written a letter to the premier on Wednesday.

He is the first ruling party leader to demand that Abdullah step down, although his father has also urged the prime minister to resign over the party's worst election setback in its 50-year rule.

Islamists and leftist opposition parties won control of five of Malaysia's 13 state assemblies and just over a third of federal parliament, prompting speculation that Abdullah could quit, but he has refused to go.

Abdullah was sworn in as leader on Monday for a second five-year term. He succeeded Mahathir in late 2003 following the latter's retirement after 22 years in office.

In the letter, Mukhriz said Abdullah should take full responsibility for the huge electoral setback faced by the National Front coalition and its dominant party, UMNO.

'The only way to successfully revive the coalition, UMNO and the nation is through your resignation,' he wrote. Abdullah is also leader of the UNMO.

'There's no point denying the obvious in order to hold on to your position as the Prime Minister,' said Mukhriz, who was elected as a lawmaker for the first time at the March 8 election.

'If you do not resign in the near future, I fear that the situation will become untenable and that the Malay support for UMNO and the coalition will be a thing of the past,' he added.

Mukhriz said he had held a news conference on Monday to indirectly ask Abdullah to quit. 'That didn't seem to work,' he said, adding that he was willing to face the political repercussions of his public stand. 'I leave it to Allah to decide on my fate.' -Reuters