British Prime Minister David Cameron opened the conference with reports of attacks by pro-Kadhafi forces in the city of Misrata.
"I have had reports this morning that the city is under attack from both land and sea," he said. "Kadhafi is using snipers to shoot them [the people of Misrata] down and let them bleed to death in the street."
US Secretary of State, Hillary Clinton, also said that the allied strikes on Libya would go on until Kadhafi meets the terms of a UN resolution calling for a ceasefire and authorising a no-fly zone to protect civilians.
Ten days of Western air strikes on Kadhafi's forces have allowed rebels to push back westwards, although they were halted near the key city of Sirte on Tuesday and Kadhafi's forces swept through Libya's third city of Misrata .
Meanwhile, France, which was the first country to recognise the opposition council, is to send an ambassador to Benghazi. A French official told the French news agency, AFP, that 53-year-old Antoine Sivan is on his way to the Libyan rebel stronghold.