French President Nicolas Sarkozy hosted British Prime Minister David Cameron and their respective defense chiefs in Paris on the eve of a two-day meeting of NATO foreign ministers in Berlin with Libya high on the agenda.

A leading Sarkozy adviser, briefing reporters after the meeting, said Britain and France agreed to “show extreme strength of conviction” so that a NATO-led international coalition enforcing a no-fly zone and carrying out air strikes over Libya will have “all the means it needs.” France and Britain are leading the allied air campaign in Libya and have sought greater participation from other NATO nations, notably the United States, after three weeks of allied airstrikes have failed to rout Qaddafi’s forces.

Cameron, speaking before the Sarkozy meeting, pledged that Britain and France would leave “no stone unturned” as they look for ways to help Libya’s rebels and prevent slaughter of civilians.

Cameron said Britain and France would seek ways to halt Qaddafi’s assault against civilians in places like the besieged city of Misrata — the only city in western Libya still partially held by rebels.

“It is appalling what Qaddafi is doing in Misrata — he is murdering his own citizens, including children,” he said.

“The orders come directly from him. But NATO has taken steps, we have destroyed dozens of tanks and other armored vehicles around Misrata.” France and Britain want to encourage more defections from Qaddafi’s government — by threatening those linked to the regime with prosecutions at the International Criminal Court in the Hague — to the opposition Libyan Transitional Council, the French official said.

He said that arming the Libyan rebels does not violate a UN Security Council resolution authorizing force to protect Libyan civilians. France is not supplying the rebels with weapons, though “that doesn’t mean we don’t sympathize with those who do,” he said.

The Libyan rebels “don’t have particular difficulty in finding either the weapons they need or friends who can teach them how to use them,” said the official, without elaborating.

Meanwhile, Cameron’s office issued a statement saying Britain has decided to supply 1,000 sets of body armor from surplus British military supplies to Libya’s opposition — on top of 100 satellite phones it has already sent.

Earlier, France urged NATO to maintain military pressure on Qaddafi’s forces alongside international efforts toward a political solution. France says the alliance is not doing enough to back up the Security Council resolution.

In Britain, a UK military spokesman, Maj. Gen. John Lorimer, told reporters: “From our point of view we recognize the NATO-led operation is delivering real effect.” He declined to elaborate on whether NATO was acting quickly or efficiently enough, and deferred to the alliance.

British and French officials believe Washington’s military strength is needed to ensure the Libya mission’s success.

But the Obama administration insisted Tuesday that the US will stick to its plan to remain in the back seat.

US Secretary of State Hillary Clinton is traveling to Berlin for the NATO meeting.

The Sarkozy-Cameron meeting in Paris came after an international conference in Doha, Qatar including the UN secretary-general and other top Western and Arab envoys to discuss ways to end the Libyan crisis.

The statement from Cameron’s office said that it welcomed an agreement in Doha to support the Libyan opposition — notably through the creation of “trust fund” to channel in financial aid.

British Foreign Secretary William Hague said Wednesday the military intervention in Libya will end with Qaddafi’s departure, but he cannot predict how soon that could happen. He said he believes Libya’s opposition is “steadily becoming better organized.” “Do not underestimate what is being achieved here,” Hague told the BBC from Qatar. “With the airstrikes we have conducted, thousands of lives have been saved.”