- Video report by ITV News Correspondent Sejal Karia
South Africa's ruling party, African National Congress (ANC), has begun the process of selecting a new leader to replace scandal-prone President Jacob Zuma.
The reputation of Nelson Mandela's liberation movement has been battered by Zuma's administration that has been mired in scandal and corruption allegations.
Front-runners in the race to take over from Zuma, whose second term is up, are deputy president Cyril Ramaphosa and Nkosazana Dlamini-Zuma, Zuma's ex-wife.
Many claim Zuma is responsible for the party's woes and the country's economic stagnation.
He has been accused of representing the "betrayal of the South African dream".
Under Zuma, unemployment has risen to nearly 30% and economic growth has slumped. More than 55% of the country lives below the poverty line.
He denies the allegations and is urging his party to unite behind his successor.
"We must attend to enormous challenges facing our movement," Mr Zuma told the gathering of thousands of delegates.
He claimed that "theft and corruption" in the private sector is just as bad as in government and that "being black and successful is being made synonymous to being corrupt".
Mr Zuma also said "greed is posing a serious threat" to the party and warned that the ANC could "implode".
He also rejected the party's "petty squabbles" that have distracted the ANC from its work and said challenges to inclusion are "killing our movement".
"A heavy responsibility lies upon the shoulders of delegates here... to renew our movement and to restore its timeless values," Zuma said.
Divisions within the ANC run so deep that analysts say either outcome, Mr Ramaphosa or Ms Dlamini-Zuma, could mean the end of the ANC's dominance as members of the losing faction could form a new party.
Observers say the party needs to restore its reputation or it could be forced into a governing coalition for the first time.
Zuma could carry on as head of state until 2019, when his term ends, or he could step down or be ousted before then by the new party leader ahead of the general elections.
Leadership candidate Mr Ramaphosa has pledged to crack down on corruption and get the economy back on track.
Ms Dlamini-Zuma, a doctor and former government minister, has promised to bring more black South Africans into the fold through "radical economic transformation".
Some South Africans worry that she would be influenced by her ex-husband and perhaps shelter him from prosecution.
The growing frustration around Mr Zuma led the party to suffer its worst-ever performance in municipal elections in 2016, with its vote share falling below 60% for the first time.
ANC delegates are set to cast their vote on Sunday.