Canadian fighter jets have flown their first mission as part of the international effort to enforce a no-fly-zone over Libya.

Four CF-18 fighter aircraft and two CC-150 Polaris refueling planes departed from a base in Trapani, Italy on Monday morning, to conduct patrols and escort fighters of another nation.

Defence Minister Peter MacKay said the aircraft returned safely to base.

"These high-level, strategic strikes are to dispose of airfields and the use of Libyan military assets that the Gadhafi regime is using to target civilians," MacKay said at a briefing at National Defence headquarters.

"Simply put: We want to disable their air force."

MacKay stressed that the mission did not involve attacking ground targets.

The Canadian jets are part of an effort authorized by the United Nations Security Council on Friday to restrict airspace over Libya and to minimize attacks by forces loyal to Libyan leader Moammar Gadhafi against that country's civilian population.

"This is being done in a very coordinated and staged fashion, and Canada right now is contributing significantly and it's appreciated," MacKay said.

In addition to the "six-pack" of CF-18s that are in the region now, MacKay said more CF-18s in Canada are at the ready to assist if needed.

"We will prepare for all contingencies but there is no set plan at this point to deploy more aircraft into the theatre. What we'll do is essentially watch and wait to see how the no-fly-zone requirements there are met," he said.

Debate

Meanwhile, the House of Commons continued Monday to debate Canada's military role in the Libyan crisis.

The government is planning to introduce a motion during the debate that calls all parties to support the military deployment.

There are also approximately 140 Canadian military personnel, including pilots and air crew, deployed as part of that mission. HMCS Charlottetown, which left Halifax on March 2, is also stationed nearby in the Mediterranean Sea.

NDP Leader Jack Layton said he wants to see an exit strategy. He called on the prime minister to allow opposition members to be involved and keep an eye on the conflict.

"Not only must Parliament debate the Libyan question on an urgent basis," Layton told the Commons, "it's essential to draw a lesson from the war in Afghanistan and give parliamentarians a surveillance and oversight role."

MacKay said the debate will be an opportunity for opposition parties to show their support for the government's decision.

The operation began with air strikes by French fighter jets on Saturday, followed by a barrage from U.S. and British warships.

Personnel from Belgium, Denmark and Spain are said to be involved in the operation, with Qatar representing the only participating Arab nation so far.

MacKay said it is a U.S.-led operation for the moment, but discussions are taking place in Brussels on who will take over command and control of the multinational operation.

"It is my understanding that this mission may very well morph into a NATO-led mission," said MacKay.

Under the terms of the UN Security Council no-fly zone resolution, "all necessary measures" can be invoked to protect Libyan civilians.

"Gadhafi has clearly demonstrated wanton disregard for the well being of his own citizens. There have been terrible casualties already," MacKay said Sunday, refusing to comment on whether the mission will eventually require Canadian soldiers on the ground.

Both MacKay and Prime Minister Stephen Harper have previously said that the air mission is not without dangers and there is no guarantee Canadian troops will escape unharmed.

With files from The Canadian Press