Muammar Gaddafi has accepted a roadmap for ending the conflict in Libya including an immediate ceasefire, the African Union said on Monday, but an opposition representative said it would only work if Gaddafi left power.
South African President Jacob Zuma, who met Gaddafi at the head of a delegation of African leaders, urged NATO to stop air strikes on government targets to "give ceasefire a chance".
Earlier truce offers from Gaddafi have come to nothing and the rebels, who took up arms across the east and in some towns in the west after the Libyan leader crushed protests in February, have said they will accept nothing less than an end to his 41 year-old rule.
"The brother leader delegation has accepted the roadmap as presented by us. We have to give ceasefire a chance," Zuma said, adding that the African delegation would now travel to the eastern city of Benghazi for talks with anti-Gaddafi rebels.
Asked if the issue of Gaddafi stepping down was discussed, Ramtane Lamamra, AU Commissioner for Peace and Security, told reporters: "There was some discussion."
However he added: "I cannot report on confidential discussions because first of all I was not part of them, and I think they have to remain confidential between the parties involved."
Officials from NATO, which stepped up attacks on Gaddafi's armour on Sunday to weaken a bitter siege of Misrata in the west and disrupt an advance by his troops in the east, were not immediately available for comment on Zuma's ceasefire appeal.
The British-based representative of the Libyan opposition leadership, Guma al-Gamaty, said it would look carefully at the AU plan, but would not accept any deal designed to keep Gaddafi or his sons in place, Britain's BBC reported.
Libyan officials have repeatedly said Gaddafi will not quit.
Zuma met Gaddafi for several hours at the Libyan leader's Bab al-Aziziyah compound with four other African heads of state.
The AU's Lamamra said the proposal included the delivery of humanitarian aid, protection of foreigners, dialogue between all parties and "the establishment of an inclusive transition period with a view to adopting and implementing necessary political reforms".
He said the AU was ready to help with the deployment of a ceasefire monitoring mechanism and could work alongside the United Nations and the Arab League.
Asked if he feared rebels might reject the plan, Lamamra said: "We believe what we have proposed is broad enough to launch negotiations ... What we need is for them to accept that we are people of good will."
"It's not up to any outside force, even the African Union itself, to decide on the behalf of the Libyan people on who the leader of the country should be," Lamamra told a news conference in the early hours of Monday morning after the AU talks.
The rebels have previously rejected a negotiated outcome to what has become the bloodiest in a series of pro-democracy revolts across the Arab world that have ousted the autocratic leaders of Tunisia and Egypt.
NATO INTENSIFIES ATTACKS
NATO, mandated by the United Nations to protect civilians in Libya from attacks by Gaddafi's forces, said it had increased the tempo of its air operations over the weekend, after rebels accused it of responding too slowly to government attacks.
The insurgents hailed the more muscular approach.
The NATO strikes outside Ajdabiyah on Sunday helped break the biggest assault by Gaddafi's forces on the eastern front for at least a week. The town is the gateway to the rebel stronghold of Benghazi 150 km (90 miles) north up the Mediterranean coast.
A Reuters reporter saw six burning hulks surrounded by 15 charred and dismembered bodies in two sites on Ajdabiyah's western approaches which rebels said were hit by air strikes. "NATO has to do this to help us every single day. That is the only way we are going to win this war," said 25-year-old rebel Tarek Obeidy, standing over the bodies.
The government attack, which began on Saturday, included a fierce artillery and rocket bombardment, while some of Gaddafi's forces, including snipers, penetrated Ajdabiyah. Rebels cowered in alleys for several hours under the bombardment.
The corpses of four rebels were found dumped on a roadside.
"Their throats were slit. They were all shot a few times in the chest as well. I just could not stop crying when I saw them," said rebel Muhammad Saad. "This is becoming tougher and tougher."
But by afternoon rebels looked back in control of Ajdabiyah, commanding key intersections, and fighting had died down.
Ajdabiyah had been the launch point for insurgents during a week-long fight for the oil port of Brega 70 km (45 miles) further west, and its fall would be a serious loss.
Gaddafi, making his first appearance to foreign media in weeks, joined the visiting African leaders at his compound.
He then climbed into a sports utility vehicle and was driven about 50 metres (yards) where he waved through the sunroof and made the "V" for victory sign to a crowd of cheering supporters.
The appearance, his second in two days, and his upbeat demeanour, confirmed the impression among analysts that his circle has emerged from a period of paralysis and is preparing for a long campaign, another sign mediation will be difficult.
Analysts predict a drawn-out, low-level conflict possibly leading to partition between east and west in the sprawling North African Arab state, a major oil and natural gas producer.
NATO's commander of Libyan operations, Canadian Lieutenant General Charles Bouchard, said after Sunday's air attacks: "The situation in Ajdabiyah, and Misrata in particular, is desperate for those Libyans who are being brutally shelled by the regime."
Asked for comment on the ceasefire announcement, a British official repeated a well-worn statement: "We will judge Gaddafi by his actions not his words." (Additional reporting by Michael Georgy in Ajdabiyah, Mariam Karouny in Beirut, Richard Lough in Rabat, Christian Lowe in Algiers, Stella Mapenzauswa in Johannesburg, Foo Yun Chee in Brussels and Karolina Tagaris in London; writing by Barry Moody and Philippa Fletcher; editing by Miral Fahmy)