In Ajdabiya, pro-Gaddafi forces have pushed back rebels in fierce fighting.
Nato says its planes destroyed 25 government tanks on Sunday alone.
The African Union's road map calls for an immediate cease-fire, opening channels for humanitarian aid and talks between the rebels and the government.
"The brother leader [Col Gaddafi] delegation has accepted the roadmap as presented by us," Mr Zuma declared.
"We have to give the ceasefire a chance," he said, after several hours of talks.
The details of the plan would be set out later in a statement, Mr Zuma said.
The British-based representative of the Libyan opposition leadership, Guma al-Gamaty, has told the BBC that they would look carefully at the AU plan, but that any deal designed to keep Colonel Gaddafi or his sons in place would not be acceptable.
Tanks destroyed Nato air strikes have been continuing: the alliance says its planes destroyed 25 government tanks on Sunday alone.
Eleven were reportedly destroyed as they approached Ajdabiya and 14 were destroyed earlier near Misrata, the only city in western Libya still in rebel handsContinued