The ruling African National Congress (ANC) is divided into rival factions as delegates prepare to meet next month, analysts have said.
The party, which has governed the country since the end of apartheid in 1994, will elect its new leaders, including its president and deputy, at a conference in December.
"The ANC today is much more divided than it has ever been before," political analyst Shadrack Gutto told Anadolu Agency.
Gutto, the former director of the Centre for African Renaissance Studies at the University of South Africa, said there are many contenders for the top positions, creating factions that threaten the party's grip on power.
"In my view, the ANC will be weaker after its party elections but that does not mean it will not remain a major political party," Gutto said.
Andre Duvenhage, a political science professor at South Africa's North-West University, agreed on divisions within the party.
"There are about seven candidates contesting for the position of ANC president, which has created divisions in the party along party branches and provinces," he said.
Jacob Zuma, 75, has served as the country's president since 2009, having been elected ANC leader two years earlier. His time in office has been marked by allegations of corruption against the former communist.
Duvenhage said it remained to be seen if the ANC would still be a unified party after the conference.
Although several candidates will stand for the presidency, the race will narrow to Deputy President Cyril Ramaphosa, former AU Commission Chairman Nkosazana Dlamini-Zuma and Treasurer-General Zweli Mkhize.
- INTERNAL POLITICS
Ramaphosa's campaign has mostly revolved around anti-corruption and good governance.
Dlamini-Zuma has been telling supporters she will bring them economic freedom by redistributing land acquired from whites, a highly contentious issue as most of it still remains in the hands of white South Africans.
The ANC's support base has declined in recent years but it still has a majority in parliament, holding 249 seats in the 400-seat assembly.
That means the next ANC president will almost certainly become South African president.
Divisions within the party could also weaken it in 2019 parliamentary and provincial elections.
However, ANC national spokesman Zizi Kodwa played down splits amid the party's followers. "It's internal politics, there are no divisions," he said.
"The ANC is a people's organization and will remain united even after the conference."
Critics of the ANC accuse the party of failing to discipline Zuma over a series of corruption scandals.
Most recently, allegations of a corrupt relationship with the influential Indian Gupta family have dogged the president. Zuma denies the allegations.
He has survived eight no-confidence votes in parliament thanks to his party's comfortable majority despite mass protests calling for his removal.
Experts say Zuma's ex-wife, Dlamini-Zuma, will protect him from prosecution if she becomes president.
