Malaysia's parliament will convene Monday to decide on the country's next prime minister after days of horse-trading failed to break an impasse, said Mahathir Mohamad, whose resignation triggered the crisis.

Mahathir quit this week as premier and the government collapsed, following a bid to form a new coalition without his designated successor Anwar Ibrahim and stop him becoming leader.

Mahathir, at 94 the world's oldest leader, and Anwar are now locked in a power struggle, reviving a rivalry that has shaped politics in the Southeast Asian nation for two decades. The king appoints the prime minister and had interviewed the country's MPs to work out who they backed, but Mahathir said no candidate with enough support emerged.

A candidate must have the backing of at least 112 MPs to become premier. The king "says that the right forum will be parliament," said Mahathir on Thursday, following a morning meeting with the monarch.

He added the legislature would sit on Monday to determine who has sufficient backing to become premier. "However if the (parliament) fails to find a person with a majority, then we will have to go for a snap election," added Mahathir, who was appointed interim leader following his resignation.

He added his party might nominate his ally Muhyiddin Yassin, who was interior minister until the government collapsed, as a candidate. Three parties from the former ruling coalition have already put Anwar's name forward.

In his first comments since the crisis erupted, Mahathir said Wednesday he wanted to form a unity government and was willing to return as premier if he had enough support -- but political leaders rejected that idea.

The drama began at the weekend when some MPs from the then ruling "Pact of Hope" coalition, which stormed to a historic victory in 2018, sought to join opposition groups and form a new government. Mahathir and Anwar's stormy history has shaped Malaysian politics ever since Mahathir -- during a first stint in office in the 1990s -- sacked Anwar as his deputy, and he was jailed on dubious sodomy charges.

They reconciled ahead of the 2018 polls to oust a corruption-plagued coalition led by Najib Razak, but many were sceptical Mahathir would stick to a vow to hand power to Anwar.