BRUSSELS (AFP) – The United States and key allies France and Britain are struggling to hammer out a new command structure for Libyan military operations amid divisions over the role NATO should play.

US President Barack Obama, in El Salvador wrapping up a tour of Latin America, admitted Tuesday it would take a while to forge agreement on the major issue hanging over coalition strikes against Libyan strongman Moamer Kadhafi.

"I would expect that over the next several days we will have clarity and a meeting of the minds of all those who are participating in the process," Obama said, as NATO ambassadors in Brussels failed to reach a deal.

France, which has resisted calls to give NATO control of the mission, called for the creation of a special political committee of foreign ministers from coalition countries to oversee the operations, with Arab participation.

French Foreign Minister Alain Juppe said the committee had the support of Britain and would "meet in the coming days in Brussels, London or Paris, and continue to meet regularly to show clearly that political oversight is there."

The White House said that Obama, French President Nicolas Sarkozy and British Prime Minister David Cameron had all agreed in telephone calls that NATO should play a "key role" in the future command structure.

But ambiguities remained, with France saying that Sarkozy had agreed with Obama on how NATO command structures would be used to support the coalition, but providing no specifics.

The United States suggested the eventual structure could resemble allied operations in Afghanistan, where NATO's International Security Assistance Force (ISAF) has commanded in the past in tandem with the US military.

"NATO has lot of experience in working with non-NATO partners in complicated international efforts, whether it's ISAF or KFOR in Kosovo," a senior US administration official told reporters.

"We are confident that we will be able to work out an effective mechanism that takes advantage of the practical capacities that NATO can bring to bear."

This mechanism would also make clear "that NATO is only a part of this effort and it does involve a wider coalition which already involves some Arab participation and I believe is going to involve wider Arab participation in the coming days," the source said.

"All I can say at this stage is we're still in the process of sorting through the exact structure," the official added.

In a phone conversation with Recep Tayyip Erdogan, prime minister of influential Muslim-majority NATO member Turkey, Obama himself highlighted the alliance's "unique multinational command and control capabilities."

US Secretary of State Hillary Clinton told ABC News in an interview "I'm very relaxed about it" and that she thought discussions were "moving forward in the right direction, and we will have what we need in the next few days."

"Those who are members of NATO want to see a role for NATO," she explained. "But we also want to integrate our other partners. We don't want those who are not in NATO to feel that they're on the outside looking in."

France, whose fighter jets launched the first salvos in the campaign against Kadhafi on Saturday, has resisted handing the baton to NATO, fearing a backlash from the Arab world if the alliance intervenes.

But the United States says it is eager to hand over command as soon as possible. "I have absolutely no doubt that we will be able to transfer the control of this operation to an international coalition," Obama said Tuesday.

At their meeting in Brussels, NATO ambassadors agreed to use naval and air power to enforce an arms embargo on Libya and to endorse operational plans to help enforce the UN-mandated no-fly zone.

Diplomats said it would take a few more days for NATO to decide whether to activate its participation in the no-fly zone, or take command of military operations.

US, French and British warplanes and warships have led the strikes against Kadhafi's regime since Saturday, but Britain, Canada, Italy and several other allies had been pushing for NATO to take command of operations.

Turkey had blocked the approval of NATO operational plans for a no-fly zone over Libya on Sunday, as it criticized the scope of the Western-led operation, which has included strikes on Kadhafi forces.

Germany has also refused to join the intervention in Libya, abstaining from voting for the UN Security Council resolution that approved "all necessary measures" to protect Libyan civilians from Kadhafi forces last week.