South Africa is braced for the roughest and most bitter elections since the end of apartheid after a group of senior dissidents from the ruling party, backed by about 6,000 chanting supporters, ended weeks of speculation and announced that they were setting up a new political party to oppose the mighty African National Congress (ANC).

The decision by supporters of Thabo Mbeki, the ousted former President, sets the stage for a gruelling campaign for the 2009 polls as former antiapartheid comrades angrily turn on each other — the latest twist in a three-year struggle for the soul of the ANC, the party that overthrew white minority rule and carried Nelson Mandela to power in 1994.

Barely had the starting gun fired before the insults began flying. The mainstream movement immediately hit back with a huge rally in Soweto yesterday intended to show that it still spoke for the majority. More than 25,000 supporters, bearing the black, green and yellow colours of Africa’s oldest liberation movement, wildly applauded as its leader, Jacob Zuma, hurled insults at the dissidents.

Mr Zuma accused the splinter group, led by the former Defence Minister, Mosioua “Terror” Lekota, of being a “bunch of bigamists” for sharing a platform with opposition parties at a weekend national convention before the end of an internal ANC dispute procedure.

“Even before the divorce has concluded, they have announced they will be getting married to the Democratic Alliance and other opposition forces to form a coalition,” Mr Zuma told the Sowetan faithful. The dissidents, who intend to name the new party in the next few days, gave a warning that they planned to create a real rival to the ANC and fight to win next year’s election, scheduled for April.

Mbhazima Shilowa, the former premier of the country’s richest province, Gauteng, where the wealthy cities of Johannesburg and Pretoria are located, told reporters: “We do not underestimate the work that lies ahead . . . we want to become the next government in the provinces and at the national level.”

Many political analysts fear that the campaign could now turn violent and seriously damage the country’s reputation for stability, given the depth of hostility between the two camps. At a recent rally outside Johannesburg, ANC supporters manhandled and jostled dissidents and chanted “Kill Lekota”, adapting the once infamous “Kill the Boer” antiapartheid slogan.

Mr Shilowa and Mr Lekota, a former ANC secretary-general who, like Mr Mandela, was imprisoned on Robben Island, are believed to have lined up political and financial support from top black businessmen who are worried that a Zuma-led government would be in thrall to his left-wing backers in the unions and grassroots.

On the eve of the conference, to which all opposition parties were invited, another senior ANC official defected in a carefully orchestrated move. Others are expected to follow over the coming weeks. Mr Mbeki has said that he will endorse neither camp, indicating that he understands the reasons for his loyalists’ anger.

At the convention centre in the wealthy northern Johannesburg suburb of Sandton, Lekota supporters carried placards reading “We are claiming our country back” and “Rise and be counted”. It remains to be seen if the new party can mobilise support in the townships, where Mr Zuma is hugely popular.

At the rally yesterday Mr Zuma, who is accused of high-level corruption, spoke in his native Zulu, saying that he would make education and the battle against soaring crime his priorities. The bookish Mr Mbeki always spoke in English and angrily denied that his Government was failing the people in any areas.

Mr Zuma, 66, poured scorn on the dissidents. He said that they had no policies other than wanting to remain in power. “We can’t wait for them to form their own party so that we can engage them in debate, not in anger . . . The ANC is still the party it was in the old days. We are going to win the upcoming election with an overwhelming majority, as we have done in previous years,” he said to thunderous applause.

After he ousted Mr Mbeki from the leadership of the ANC in December last year, Mr Zuma automatically became the party’s candidate for President at the next polls. Mr Mbeki stepped down from office in September after he was accused of plotting to block a Zuma presidency. He was replaced by an ANC stalwart, Kgalema Motlanthe, who is seen as only a caretaker President until Mr Zuma can win a popular mandate.

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