The decision came as Mr. Zuma refuses to stand down even after police raided homes of his associates, the Gupta family, in Johannesburg, the country’s commercial capital.
The Guptas, who have been named in a series of corruption probes, are said to be associates of Mr. Zuma, who has led South Africa since 2009.
Some members of the ANC have long asked Mr. Zuma to step down, and the party itself formally took a position on the matter by asking Mr. Zuma to resign.
The party’s Treasurer-General, Paul Mashatile, said on Wednesday that the party is starting “a new era.”
“The conference of ANC has created new hope. Our people want to see change. We want to go with renewal,” Mr. Mashatile said.
He added that the deadline given to Mr. Zuma would expire on Wednesday night.
If Mr. Zuma resigns, the cabinet would stay, Mr. Mashatile said, but should he be removed via a no-confidence vote, the entire cabinet would have to be removed, the ANC treasurer-general added.
Mr. Zuma appeared live on SABC a moment ago to discuss the allegations against him. He denied allegations of wrongdoing and vowed not to resign.
“No, I will not resign,” he said.
The ANC said the parliament could elect another president as soon as Thursday if Mr. Zuma agrees to step down.
Thursday’s no-confidence votes is coming barely six months after Mr. Zuma survived the ninth attempt to remove him from office.
Out of the total 384 parliamentarians that voted in the August 8, 2017 no-confidence motion, about 177 expressed no confidence in Mr. Zuma.
More than half of the voters, 198, opposed the motion while nine lawmakers abstained. The voting shows that the anti-Zuma coalition got some ANC votes but not enough to get a majority to remove the president.
If the Thursday’s motion goes on as planned, it would be the ninth no-confidence votes in Mr. Zuma’s less than nine years in office.
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