Zuma made the comment Tuesday after returning home from meeting with Gadhafi in Tripoli Monday. Zuma was trying to broker a peace deal between the Libyan government and rebel fighters.
Zuma told Libyan media Monday that Gadhafi wants a cease-fire to include an end to NATO bombing, terms the rebels rejected last month after an earlier mediation mission by the South African president. The rebels, whose central demand is Gadhafi's resignation, quickly rejected this latest offer.
Meanwhile, the U.N. humanitarian aid coordinator for Libya told Reuters news agency that it is just a matter of weeks before dwindling food supplies result in a "critical situation."
On Monday, eight Libyan army officers held a press conference in Rome, claiming they are among about 120 soldiers who recently defected from Libya.
The men read an appeal to fellow army officers and top police and security officials, urging them to abandon Gadhafi's government.
Earlier Monday, NATO Secretary-General Anders Fogh Rasmussen said Gadhafi is "increasingly isolated" at home and abroad with close allies "departing, defecting or deserting" the Libyan leader.
NATO forces have been operating under a U.N. Security Council mandate to protect civilians from Gadhafi's attempts to crush the uprising.