Johannesburg  - South Africa's ruling African National Congress' (ANC) was in full damage control mode Tuesday following the shock resignation of 11 cabinet ministers and three deputy ministers after President Thabo Mbeki's ousting by the party.

"We think that this is under control. There's no crisis," ANC secretary-general Gwede Mantashe told a hastily-convened news conference in Johannesburg, despite the mass walkout by Mbeki loyalists appearing to catch the party off guard.

While the ANC had tried to convince the ministers against resigning, some had felt compelled "as a matter of conviction" to resign along with Mbeki. Others had done so as a matter of procedure, Mantashe said.

Six ministers had refused to return to serve under ANC deputy leader Kgalema Motlanthe, who is expected to be elected acting president by parliament on Thursday. They include Phumzile Mlambo-Ngcuka, Defence Minister Mosiuoa Lekota and Public Enterprises Minister Alec Erwin.

The rest had resigned because they had been appointed by Mbeki and were waiting to be reappointed by Motlanthe, Mantashe said.

Finance Minister Trevor Manuel, one of the world's longest-serving and most popular finance ministers, was among those who quit but later gave notice of his return, saying he was "ready to assist and serve" a new administration.

Manuel, who has been finance minister since 1996, during which time he turned massive post-apartheid debt into a string of budget surpluses, is seen as the Mbeki government's greatest asset.

His resignation caused far greater jitters in financial markets than the departure of Mbeki himself, whose powers had already been curtailed after he was ousted by Jacob Zuma as ANC leader last year.

The rand lost ground against the dollar on the news of Manuel's departure but later recovered on news of his imminent return.

Since demanding that Mbeki resign at the weekend over a court finding of political interference in Zuma's corruption case, the ANC has been batting its eyelids at his cabinet colleagues.

The Zuma camp within the party and its alliance partners is short on experienced government hands.

The resignations turned ANC leader Zuma's assurances of a "smooth transition" on its head.

Only Monday, Zuma, who is expected to take over as head of state following elections slated for April or May, had downplayed Mbeki's departure, saying "this is not a change of party but only leadership in government."

The walkout showed the fallout of factional fighting in the ruling party could be more extensive than predicted, amid reports that some Mbeki supporters may form a new party.

The bell tolled for Mbeki when a judge in the Pietermaritzburg High Court on September 12, in setting aside the corruption charges against Zuma on a technicality, inferred Mbeki had a hand in the decision to lay charges against him.

Mbeki's enemies in the ANC seized on the ruling to push for his resignation.

Mbeki has denied the allegations and approached the Constitutional Court, the country's top court, on Monday to seek leave to appeal on the grounds that the ruling was "prejudicial" to him and harmed his right to dignity.

Motlanthe, a former ANC secretary general under Mbeki and party moderate, had been seen as one of the few party leaders with enough cross-factional appeal to convince Mbeki loyalists to stay put. (dpa)