The speaker of parliament said Zuma will not give the state of the nation address in parliament Thursday and the ruling party announced the postponement of a key meeting Wednesday to discuss the president's fate.
When pro-Zuma forces in the party humiliated former President Thabo Mbeki by forcing him out of office in 2008, eight months before the end of his term, it precipitated a split in the party.
Supporters of Ramaphosa, a multimillionaire businessman who is seen as the standard bearer of the reformist wing of the party, say it is essential that Zuma is sidelined as early as possible to allow the ANC to regroup before campaigning starts in earnest for elections in 2019.
The 80-member national executive committee is seen as finely balanced between supporters of Zuma and Ramaphosa.
South African President Jacob Zuma attends an event during the 30th annual African Union summit in Addis Ababa, Ethiopia, Jan. 28, 2018. But on Tuesday, two days before this year's address, parliamentary leaders abruptly announced that it would be postponed.
The ANC's NWC conducts the day-to-day running of the party. The charges were dropped shortly before Zuma became president in 2009, but were reinstated in 2016.
Ramaphosa says this is a challenging time for our country but that he and Zuma are aware that people want and deserve closure.
Senior ANC leaders met Zuma over the weekend and urged him to step down for the sake of the party and country, but the embattled president has so far refused to go.More news: Amazon to launch delivery service to rival UPS and FedEx
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The president has resisted calls to quit over corruption allegations.
By Tuesday morning, reports circulated that President Jacob Zuma had called an emergency Cabinet meeting.
The South African president has also been linked to the controversial Indian-born Gupta family, who has been implicated in large-scale corruption and state capture.
While the legislature is due to debate a motion of no-confidence proposed by the opposition Economic Freedom Fighters party on February 22, it "may not be needed", the ANC's chief parliamentary whip, Jackson Mthembu, told eNCA television.
"There is a real sense, he concluded, the bishops were saying to Zuma: 'do not hold on; you are making things worse, could you step down now?'"
Opposition parties and civil society groups had threatened to go to court if Zuma's address is not postponed. The State of the Nation Address will be broadcast live on: Dstv Channel 408, SABC TV, eNCA, ANN7, SABC radio stations and Parliament's YouTube Channel.
Health Minister Aaron Motsoaledi said the ruling party will settle its disputes behind closed doors.
"If he doesn't resign following a recall then it will be a very chaotic situation", Ben Payton, analyst for the London-based Maplecroft consultancy, told AFP.
Zuma's presidency has been engulfed by corruption scandals.