Media playback is unsupported on your device Media caption David Cameron: "Every day Gaddafi is brutalising his own people"

Imposing a no-fly zone over Libya is "perfectly deliverable", UK Prime Minister David Cameron has said.

Mr Cameron, who attended an EU meeting on the country's crisis on Friday, said his fellow leaders were "crystal clear" Col Muammar Gaddafi should go.

The UN Security Council should consider tougher measures against mercenaries and the states they come from, he said.

But Labour leader Ed Miliband said the government had to "translate the 'no-fly zone' phrase into a plan".

Britain and France are spearheading moves to prevent further air attacks on rebels by forces loyal to Col Gaddafi.

But other countries are more cautious about the idea of any military intervention in Libya.

In a statement to the Commons, Mr Cameron said there had been "progress" at the European Council.

He added that there "should be tougher measures against [foreign] mercenaries [employed by the Gaddafi regime to fight rebels] and the states from which they come".

Do we want a failed pariah state festering on Europe's border? Of course we do not want that David Cameron Gaddafi forces bomb Libya rebelsG8 leaders consider Libya action

Mr Cameron said Col Gaddafi was "brutalising his own people and that "with time of the essence, there should be no let-up of pressure on this regime.

"We've seen the uprising of a people against a brutal dictator and it will send a bad signal if their aspirations are crushed," he said.

"Do we want a failed pariah state festering on Europe's border? Of course we do not want that."

Mr Miliband said it was disappointing the EU agreement on Friday did not mention a no-fly zone and said: "It seems to us now that the priority must be to translate the 'no-fly zone' phrase into a plan."

He asked whether other EU countries had doubts about the "workability" of the plan.

The prime minister said a no-fly zone was "perfectly practical and deliverable" but must be legally implemented, and have widespread support in the region and across the international community.

He recognised that it was not a "silver bullet" to end the crisis but said the international community had to look at what it could do to "tighten the noose" around Col Gaddafi's regime.

Bosnia 'mistakes'

Conservative MP and former foreign secretary Sir Malcolm Rifkind earlier called for an "open and urgent" supply of weapons to the Libyan rebels, to avoid repeating the "mistake" of the Bosnian war in the 1990s.

Mr Cameron said he did not rule out options but there were "important legal, practical and other issues which would have to be resolved" including a UN arms embargo.

But another Conservative MP, Edward Leigh, warned that Afghanistan showed that "arming insurgents against a regime we do not like can have incalculable consequences for the future".

"In the search for legality a Security Council resolution is the only real universally accepted basis Lord Morris, Former attorney general

He said supplying arms or setting up a no-fly zone could also lead to a civil war and "mounting moral pressure" to send in ground forces.

Mr Cameron said: "There is no intention to get involved in another war, or to see an invasion... that is not what is being looked at.

He added: "I think we will be letting down ourselves as well as the Libyan people if we do nothing and just say 'this is all too difficult'."

In the House of Lords, Lord Hannay of Chiswick, the UK's former ambassador to the United Nations, said there was a "clear" legal case for imposing a no-fly zone, even without a UN resolution.

"I know drafting UN resolutions is quite complicated but it doesn't, frankly, take two weeks," he said.

"It is only when you have got a resolution on the table that people are forced to take a position on it and with the Arab League now supporting a no-fly zone, the situation should change tactically quite a lot."

But Labour's Lord Morris of Aberavon, attorney general during the Kosovo conflict in the late 1990s, said: "In the search for legality a Security Council resolution is the only real universally accepted basis, difficult as this may be to get sometimes."

Foreign ministers from the Group of Eight major world powers are meeting in Paris to consider whether to back calls for a no-fly zone over Libya.

The Arab League supports a UN mandate but Russia has so far opposed military intervention and the US, Italy and Germany have also voiced reservations.