Gwede Mantashe, secretary general of the ANC brushed off suggestions that Mugabe could only be forced out through a military invasion.
"I don’t think invading Zimbabwe or sanctions would work," he said.
"What will we do to make Mugabe retire? We will persuade him," Mantashe said, according to Sapa news agency.
Mantashe said that South Africa would prefer to deal with Zimbabwe "on a government-to-government level and on a party-to-party level".
He said the ANC leadership had discussed Mugabe’s reasons for wanting to stay in power, saying the 84-year-old was afraid of being arrested and charged with war crimes like former Liberian president Charles Taylor.
Taylor, who was Liberia’s president from 1997 to 2003, was forced into exile in Nigeria before being extradited to the Hague.
"The Hague has taken a number of African people. Mugabe can’t be given any guarantees for his safety in retirement," Sapa quoted Mantashe as saying.
Mugabe has ruled Zimbabwe since independence from Britain in 1980, when he was hailed as a liberation hero.
Now the opposition accuses his party of orchestrating deadly political attacks while the country crumbles.
Several mainly Western countries have called on him to step down. – AFP