Libya's eastern rebel stronghold Benghazi braced tonight amid rumours that Muammar Gaddafi's troops were within striking distance of the city and planning an evening assault.

Hundreds of men, some riding in pick-up trucks mounted with machine guns, flooded out of the city, responding to a call from Benghazi's rebel-run radio to man their posts.

Several loud explosions, some of them followed immediately by anti-aircraft fire, were heard inside Benghazi and new checkpoints sprang up as word spread that the Libyan leader's forces could be near by.

There was no immediate confirmation that Gaddafi's forces had moved closer to the city and his deputy foreign minister, speaking in Tripoli, denied that there were any plans to attack the rebel bastion.

"We have no intention of entering Benghazi," Deputy Foreign Minister Khaled Kaaim told reporters late today.

He said Gaddafi's government intended to adhere to a ceasefire they had announced earlier in the day, which rebels said had been violated continuously since its announcement by loyalist forces.

In Benghazi, preachers took to loudspeakers at mosques across the city to chant religious phrases and rally the city's residents. Communication inside the city was virtually impossible, with cellphone reception shut down completely.

"We heard it on the news, that they are coming," said one resident manning a newly-set up checkpoint, who declined to give his name.

"We came here to protect the place, just in case" added the man, his face wrapped in a chequered scarf. "We're not scared, we either stay here or we die."

Benghazi's rebel-held radio called on the city's fighters to head some 80 kilometres south to the village of Al-Magrun, to "block Gaddafi's forces."

"We calls on the soldiers and officers to take their arms and go to Al-Magrun to defend the entrance to Benghazi," a message carried on the station said.

"We call on them to go there now and very quickly," the statement said.

A flow of traffic, including Grad rockets mounted on trucks and at least one tank could be seen moving southward outside Benghazi, along with hundreds of fighters.

Mohammed Gihani, 17, was heading towards Al-Magrun armed only with a knife.

"I don't have any other weapons, but if all I can do is this," he said, drawing his hand across his neck, "then I'll do it."