S. Africa's Mbeki Agrees to Step Down

The tensions combined with rancor over the court case against Zuma, who for seven years has been investigated on corruption allegations in relation to a multimillion-dollar arms deal.

In 2005, Zuma's financial adviser was convicted of soliciting bribes on Zuma's behalf. Mbeki then fired Zuma as deputy president, a move some analysts say energized Mbeki's opponents, who saw him as high-handed and ruthless. Zuma was charged the same year, but the case was dropped on a technicality.

Zuma, 66, staged a political comeback in December, wresting control of the ANC presidency from Mbeki. Days later, prosecutors refiled charges against Zuma, outraging his backers. The tipping point came this month, analysts said, when a high court judge dismissed the charges and suggested that Mbeki had been part of a political scheme against Zuma. Days later, prosecutors said they would appeal the ruling, a move the ANC decried as an extension of the "relentless pursuit of Jacob Zuma."

Those events overshadowed Mbeki's successful negotiation of a power-sharing deal in Zimbabwe.

On Saturday, Mantashe said the ouster was "not a punishment" for the man he called "comrade Mbeki." But some observers said it smacked of score-settling.

"The ANC has made its own internal problems a crisis for the country," Helen Zille, leader of an opposition party, the Democratic Alliance, said in an interview on the television network SABC. "Let's cut through all the clutter and say that this is exactly the political solution that Jacob Zuma has always wanted. It's about revenge."

The political drama has seemed to only boost the popularity of Zuma, whose impoverished, rural roots have earned him the adoration of South Africa's poor and working classes. Zuma, a former freedom fighter who was also exiled, offers a stark contrast to Mbeki: Unfailingly charismatic and approachable, he had little formal education and often speaks in Zulu, a language spoken by a quarter of South Africans.

Zuma has strong support from South Africa's unions and the Communist Party, which decry the economic policies that they say have benefited few. That has caused jitters among South Africa's business community and foreign investors.

But despite Zuma's alliances, political analysts say it is unclear what route his presidency would take. A senior Zuma ally recently told the Financial Times that his camp, once in power, would seek "a complete review of the conservative strategies we've pursued -- all of them." Zuma, however, has tried to reassure investors that he is committed to growth and the private sector.

Zuma's union and Communist Party supporters "think he's more open to engagement" than Mbeki, said Adam Habib, a political science professor at the University of Johannesburg. "Do I think suddenly policy is going to move sharply to the left? No, policy itself is a product of a much more complex range of things."

Whether Zuma will take over Mbeki's role as a regional power broker and an international advocate for Africa is another question. Political analysts said the situation is particularly precarious in Zimbabwe, where Mugabe and opposition leaders signed a peace deal last week but are deadlocked over the distribution of cabinet positions.

Zuma has criticized Mugabe for refusing to step down after disputed elections in the spring.

Mantashe said Saturday that Mbeki would continue as mediator in those negotiations.

"That doesn't have the same cachet," said Princeton N. Lyman, a former U.S. ambassador to South Africa and a fellow at the Council on Foreign Relations in Washington. "That's a problem, because that mediation is reaching a crisis point."