Senior US Senator John McCain paid a visit to the Libyan rebel headquarters in their eastern stronghold city of Benghazi on Friday, an AFP correspondent said.

McCain was mobbed on arrival at the courthouse in the centre of the city by a crowd of about 50 people, who chanted, "Libya free, Gaddafi go away -- thank you America, thank you Obama."

They also chanted: "The nasty Gaddafi has left and McCain came."

The senator was expected to hold talks with leaders of rebels' Transitional National Council (TNC) later in day.

McCain, the highest-ranking US politician to visit Libya's rebel-held east since a popular uprising began against Muammar Gaddafi's rule in mid-February, arrived at the courthouse in a small convoy of two black jeeps.

He was accompanied by a TNC official. After 10 minutes they departed again. Neither McCain nor the official made any comments.

McCain on Wednesday urged the United States to "re-engage" militarily in the fight to oust Gaddafi, saying Washington's NATO allies lack the necessary firepower.

"We appreciate contributions from all of our allies, the efforts they're making, especially the British and the French. But the reality is the United States is NATO," McCain told the US-Islamic World Forum in Washington.

"When you say 'we're handing it over to NATO,' we're handing it over to people and countries with limited capabilities and limited assets.

"When you withdraw our most capable assets from the battlefield -- the AC-130 gunships and the A-10 air-to-ground weapons system -- then you lose a significant capability. Our allies just don't have that," he said.