The African National Congress’s national executive committee met to discuss whether to remove Mbeki, who is popular among investors but who is mired in accusations that he conspired to undermine Jacob Zuma who has since replaced him as party boss.
The move could rattle investors with whom Mbeki is popular because of his pro-business policies.
But he has been on thin ice with powerful trade unions and other supporters of Zuma, who accuse Mbeki of trying to undermine the man who replaced him as party boss.
Fired as Mbeki’s deputy president in 2005 after he was linked to alleged wrongdoing in an arms deal, Zuma defeated his former boss in a bitter leadership contest late last year and is seen as frontrunner to succeed him as head of state next year.
Mbeki is barred by the constitution from a third term as state president.
The move to oust him picked up speed after a judge last week threw out corruption charges against Zuma and said there was high-level meddling in the case. Zuma’s camp have branded the prosecution a political witchhunt by Mbeki and his aides.
Mbeki, who has consistently denied he hatched a political conspiracy against Zuma, lashed out at his critics even as the ANC’s national executive met to discuss his fate. The powerful policy-making body is dominated by Zuma allies.
"It impoverishes our society that some resort to the tactic of advancing allegations with no fact to support these," Mbeki said in a statement issued by his office. He said he was not involved in prosecutors’ decision to appeal the Zuma ruling.
Zuma has said he wants Mbeki to serve out the remaining months of his term, but he faces a growing chorus within the African National Congress to force Mbeki to resign or push him out in a no confidence vote in the ANC-dominated parliament.
"Zuma will have to listen to all viewpoints, but it is unlikely that the NEC will rescue Mbeki," South Africa’s Business Day newspaper quoted an unnamed NEC member as saying.
Mike Davies, Middle East and Africa analyst at Eurasia Group, speaking before The Times report emerged said worries about widening internal divisions ahead of next April’s elections may lead to more moderate NEC members to support Mbeki.
"However, the opportunity for the supporters of ANC president Jacob Zuma, who dominate the NEC, to take revenge on Mbeki could be difficult to resist. Mbeki’s position hangs in the balance," Davies said in a research note.
Forcing out Mbeki, credited by the business community for policies that have spurred nearly a decade of economic growth, would create uncertainty among investors.
It could prompt the exodus of loyal ministers, possibly including the popular finance minister, Trevor Manuel. And it would further divide the party that has governed South Africa since the end of white minority rule in 1994.
"If there are significant developments with Mbeki resigning and his cabinet following suit, that could lead to high political risk attached to South Africa," said George Glynos, managing director of South Africa’s ETM market analysis firm.
There is speculation that a pro-Mbeki faction could split off from the ANC and contest general elections in 2009 separately. Most analysts, however, expect the ruling party to remain intact and win another landslide victory next year.
The ANC consistently wins about two-thirds of the vote in national elections.