Cape Town — South Africa's ruling African National Congress (ANC) has called on President Thabo Mbeki to resign.

The party's National Executive Committee said in a statement on Saturday that it had decided to "recall" Mbeki before his term in office expires. Mbeki's second and final term in office was scheduled to end next April.

However, the party gave no clear roadmap of the process by which Mbeki will be replaced. South Africa's presidents are elected by Parliament.

The ANC secretary-general, Gwede Mantashe, told a televised news conference that South Africa's constitution was "silent" on what happened when a president stepped down. Parliament would now have to "look at the formula" and "develop" a system for handling the situation, he added. Mantashe said that Mbeki had "agreed that he is going to participate in the process and the formalities."

Mantashe did indicate, however, that the party had opted not to use sections of the constitution under which Parliament could either pass a formal vote of no confidence in Mbeki or remove him from office. He said the ANC wanted to "try to resolve the problem politically."

The roots of the crisis over Mbeki's leadership, and his party's loss of confidence in him, lie in allegations of bribery and corruption around a U.S.$30 billion arms deal. The controversy has, in the words of a high court judge, become a "cancer that is devouring the body politic and the reputation for integrity built up so assiduously after the fall of apartheid."

The judge was delivering judgement in a case in which prosecutors have accused Jacob Zuma, Mbeki's successor as party leader and his prospective successor as South Africa's president, of corruption arising from the arms deal.

Mantashe made it clear that the decision to recall Mbeki had been prompted by fear that Mbeki, his cabinet and prosecutors would try to reverse a finding by the judge which suggested that cabinet ministers - and by inference Mbeki - had improperly influenced prosecutors in Zuma's case.

Mantashe said prosecutors and the cabinet had been "hitting at the core issues" when they announced this week they wanted to contest the finding. The party wanted to ensure that "contestations" within the party were minimised. "We are trying to bring back stability and certainty," he said.