American officials have held face-to-face talks with representatives of Colonel Muammar Gaddafi's government, as the NATO-led bombing campaign in Libya continues.
The BBC reports the State Department said the meeting reiterated its demand with a "clear and firm" message that Colonel Gaddafi step down, and did not involve any negotiations.
"The message was simple and unambiguous - Gaddafi must leave power so that a new political process can begin that reflects the will and aspirations of the Libyan people."
The US did not give the location of the talks, but Libya said they had taken place on Saturday in neighbouring Tunisia, the BBC says.
Libyan government spokesperson Moussa Ibrahim hailed the talks as an important step in repairing relations with the US.
"We support any dialogue, any peace initiative as long as they don't decide Libya's future from without," he told journalists in Tripoli.
On Monday, rebels said they had pushed government troops westwards after seizing back most of the town of Brega.
The Libyan government denied the claim, insisting that the key oil refinery town was still firmly under its control.
