Durban mayor James Nxumalo's position as chairman of the ANC's biggest region has been set aside and new elections have been ordered.
The decision follows two weeks of allegations that proper election rules were flouted and that money was used to influence votes.
Nxumalo defeated Zandile Gumede by 253 votes to 212 at an elective conference last month.
The decision, announced by ANC KwaZulu-Natal secretary- general Sihle Zikalala in Durban yesterday, stopped just short of declaring the elective conference null and void.
Zikalala said the decision was taken after a recommendation from the ANC's head office.
A date for a new conference has not been set.
Party members marched to the ANC's provincial headquarters last week protesting Nxumalo's victory.
They claimed that more than 200 delegates had been paid R4200 each to vote for Nxumalo.
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