WASHINGTON - (AP) - The United States welcomed a partial handoverfor the Libyan air campaign to NATO on Thursday, but the alliesapparently balked at assuming full control and the U.S. militarywas left in charge of the brunt of combat.

NATO agreed to take over command of the newly established no-flyzone over Libya, protective flights meant to deter Libyan strongmanMoammar Gadhafi from putting warplanes in the air. That leaves theU.S. with responsibility for attacks on Gadhafi's ground forces andother targets, which are the toughest and most controversialportion of the operation.

The U.S had hoped the alliance would reach a consensus Thursdayfor NATO to take full control of the military operation authorizedby the United Nations, including the protection of Libyan civiliansand supporting humanitarian aid efforts on the ground. It was notimmediately clear when the allies could reach agreement on thematter.

"We are taking the next step: We have agreed along with ourNATO allies to transition command and control for the no-fly zoneover Libya to NATO," Secretary of State Hillary Rodham Clintonsaid.

"All 28 allies have also now authorized military authorities todevelop an operations plan for NATO to take on the broader civilianprotection mission," Clinton said.

Lines of authority were unclear Thursday night, but it appearedthe NATO decision sets up dual command centers and opens the doorto confusion and finger-pointing. U.S. commanders would presumablybe chiefly responsible for ensuring that the NATO protectiveflights do not conflict with planned combat operations under U.S.command.

The Pentagon indicated U.S. warplanes will keep flying strikemissions over Libya even if the U.S. relinquishes the lead commandrole.

Senior administration officials said the breakthrough came in afour-way telephone call with Clinton and the foreign ministers ofBritain, France and Turkey. The four worked out the way forward,which included the immediate transfer of command and control of theno-fly zone over Libya, and by early next week of the rest of theU.N.-mandated mission.

The officials, speaking on condition of anonymity to discusssensitive military planning, said the actual handover of the no-flyzone would occur in one or two days. They said NATO would have afinal operational plan by over the weekend for how it would assumecontrol over the rest of the protection mission, and that it wouldbe executable by Tuesday's meeting in London of nationscontributing to the military action.

The officials said the decision of which commanders controlwhich areas was still being worked out.

NATO's announcement came after nearly a week of U.S.-led airassaults, as the Obama administration pressed for a quick handoff.A series of disagreements, including questions of overall politicalcontrol and how aggressive the mission should be, had held up theallies' agreement.

The U.S. assumed command of the operation, which began onSaturday, largely because it alone possesses the militarywherewithal to coordinate the complex array of movements, targetingand intelligence collection that was required to enable theestablishment of a protective no-fly zone over Libya. Now thatGadhafi's air force has been grounded and his air defenses largelysilenced, the mission could be pursued under a different commandsuch as NATO.

Clinton also praised the United Arab Emirates for becoming thesecond Arab country after Qatar to send planes to help the missionto protect Libyan civilians, enforce the U.N. arms embargo on theNorth African country and support humanitarian aid efforts. TheU.A.E. will deploy 12 planes.

Clinton said she will travel to London next week to coordinatethe strategy and military operation against Gadhafi's regime.

With the costs of the campaign growing by the day and members ofCongress raising complaints over the goals in Libya, theadministration wants its allies to take the lead soon.

"We are still operating under that timeline, that it will bedays, not weeks," White House press secretary Jay Carney said.

At the Pentagon, Navy Vice Adm. William Gortney, staff directorfor the military Joint Chiefs, told reporters that the Americanrole will mainly be in support missions such as refueling alliedplanes and providing aerial surveillance of Libya. But the U.S.will still fly combat missions as needed, Gortney said.

"And I would anticipate that we would continue to provide someof the interdiction strike packages as well, should that be neededby the coalition," he added, referring to combat missions such asattacks on Libyan mobile air defenses, ammunition depots, airfields and other assets that support Libyan ground forces.

Carney was more circumspect, calling the next phase of U.S.involvement a "support and assist role," using U.S. intelligenceresources and military capabilities including electronic jamming tothrow off missiles or rockets. He did not mention any combatairstrikes.

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