Under an accelerated timeline, parliament would vote to remove Zuma from office on Thursday unless he resigns before then, Mthembu said. Lawmakers would then elect a new president immediately after the vote.
The ruling party wants Deputy President Cyril Ramaphosa to take over from Zuma, who has not responded to an ANC order to quit.
Zuma has been discredited by corruption scandals tied to an arms deal two decades ago.
South Africa’s chief prosecutor is expected to make a decision on whether to prosecute Zuma on the old charges, which were reinstated last
year after being thrown out in 2009.
In another scandal, South Africa’s top court ruled in 2016 that Zuma violated the constitution following an investigation of multi-million-dollar upgrades to his private home using state funds. The president paid back some of the money.
On Wednesday, South African police raided the residential compound of a business family suspected of using its ties to Zuma to influence Cabinet appointments and land state contracts.
Agents from the Hawks, an elite police investigative unit, entered the compound of the Gupta family in Saxonwold, an affluent neighborhood in Johannesburg.
The Gupta business family has been a flashpoint for national anger over corruption in state enterprises during Zuma’s tenure. A judicial commission is preparing to investigate the alleged graft.