Libya declared a ceasefire in the country and will comply with a United Nations resolution passed overnight, Libyan Foreign Minister Moussa Koussa said on Friday. The conciliatory message was in sharp contrast to comments made by Libyan leader Muammar Gadhafi just before the UN vote, in which he said that forces loyal to him would mercilessly attack rebels.

"We decided on an immediate ceasefire and on an immediate stop to all military operations," he told reporters. "(Libya) takes great interest in protecting civilians," he said, adding that the country would also protect all foreigners and foreign assets in Libya.

The UN Security Council, meeting in a emergency session on Thursday, passed a resolution endorsing a no-fly zone to halt government troops now around 100 kilometers from Benghazi. It also authorized "all necessary measures" - code for military action - to protect civilians against Gadhafi's forces.

Within hours of the UN vote, four European countries announced that their military forces would participate in the UN-sanctioned effort to prevent the Libyan military from using its aircraft to attack rebels and civilian non-combatants in areas of the country which it no longer exerts complete control over.

Britain will imminently start moving fighter jets to bases from where they can help enforce a no-fly zone over Libya, Prime Minister David Cameron said shortly beforehand on Friday. "Britain will deploy Tornadoes and Typhoons as well as air-to-air refueling and surveillance aircraft," Cameron told parliament on Friday.

Earlier on Friday, France, Norway, and Denmark had pledged their participation in an international military task force against forces loyal to Libyan Leader Muammar Gadhafi, responding to the United Nations Security Council vote to take direct action to end fighting between the Libyan army and rebel forces.

The UN vote came just after Gadhafi had threatened to storm the rebel bastion of Benghazi overnight, showing "no mercy, no pity," in his words. "We will come. House by house, room by room," Gadhafi said in a radio address to the eastern city late on Thursday.

Al Jazeera television showed thousands of people listening to the speech in a central Benghazi square, and then erupting in celebration after the UN vote, waving anti-Gadhafi tricolors and chanting defiance of the man who has ruled for four decades. Fireworks burst over the city and gunfire rang out.

Libyan airspace was closed to civil aviation on Friday, according to European air traffic control organization Eurocontrol, after the United Nations Security Council imposed a no-fly zone over the country.

"All flight plans for traffic wishing to operate into this airspace will be suspended," Eurocontrol said in a statement. "Therefore only those flights which are exempted from the ban, in accordance with the (UN) resolution, will be permitted to operate."

Eurocontrol, which monitors air navigation across 39 European countries, earlier said it had received information from Malta that Tripoli air traffic control had put out a notice saying it was not accepting any aircraft into Libyan airspace "until further notice". However, Eurocontrol later said it did not know whether Libya had closed its own airspace.