PARIS (Reuters) - France and Britain called on Monday for supporters of Libyan leader Muammar Gaddafi to drop him before it is "too late" and asked Libyans opposing him to join a political process to pave the way for his departure.
Leaders of the United States, France, Britain and Germany held a conference call to discuss the situation in Libya and plans for a conference in London on Tuesday, a French presidential source said.
Presidents Barack Obama and Nicolas Sarkozy, Prime Minister David Cameron and Chancellor Angela Merkel were considering a Franco-British proposal to help secure a political transition in Libya, the source said.
Foreign ministers from coalition countries taking part in the U.N.-mandated operation in Libya will meet in London on Tuesday to discuss political strategies to help bring an end to Gaddafi's rule.
U.S. foreign policy officials said the Obama administration continues to get indications that people close to Gaddafi are looking for ways to arrange for him to step down.
But the U.S. officials said they were awaiting clear and credible information about possible peace offers or defections from members of the embattled Libyan leader's inner circle.
"Gaddafi must go immediately," Sarkozy and Cameron said in a joint declaration on Monday. "We call on all his supporters to drop him before it is too late," they said, adding anybody against him should join a process for political transition.
The statement repeated France and Britain's position that Gaddafi should stand down immediately, as his government has lost legitimacy, and it said the talks in London would be key to launching a long-term political solution for the North African oil-producing nation.
It urged the Libyan National Council opposition group to open a national dialogue aimed at starting a transition toward constitutional reform and free and regular elections.
Obama, who will deliver a televised speech on Libya at 7:30 p.m. EDT (2330 GMT) on Monday, has sought to limit the U.S. role in the Libya operation.
He has said the action was designed to protect civilians, not to oust Gaddafi, but he has made no secret of his desire to see the Libyan leader go.
"There are people inside the regime who seem to recognize the serious predicament in which Gaddafi finds himself and who understand that it might be best for their country to enter a post-Gaddafi chapter in their nation's history," the U.S. foreign policy official told Reuters.
The U.S. official said air strikes by the United States and its allies are degrading the fighting capability of Gaddafi's military and the moral of his commanders and troops.
A second U.S. official said the Obama administration and more than one European leader had put out their own "significant feelers" to Gaddafi's entourage but so far the only responses they had received were deemed to be "rumors" and "nothing solid."
(Reporting by Yann Le Guernigou and Emmanuel Jarry in Paris and Mark Hosenball in Washington; Writing by John Irish and Mark Hosenball; Editing by Louise Ireland and Cynthia Osterman)