Nato divided over Libya as Britain's bill hits £250m

President Sarkozy wants a quick end to the campaign so he can declare 'victory' on Bastille Day on 14 July

Severe splits have appeared within the Nato coalition battling Colonel Muammar Gaddafi's forces in Libya, with calls for an immediate ceasefire to halt the increasing violence and allow international aid to be delivered.

The Italian Foreign Minister Franco Frattini, whose country has mounted air attacks as part of the coalition and was regarded as a "hawk", called for an "immediate suspension" of hostilities to allow food and medical supplies to go to the capital, Tripoli, and Misrata, the rebel centre of resistance.

Amr Moussa, the head of the Arab League, who had been instrumental in securing support from states in the Middle East for Nato action, has spoken of his "deep misgivings" about civilian casualties and has also pressed for a ceasefire. The French President, Nicolas Sarkozy, is pressing for success in Libya by coalition forces to be achieved in time for him to declare "victory" on Bastille Day in Paris.

The President has urged a step-up of military and diplomatic efforts to enable him to announce a successful resolution to the conflict on France's national holiday on 14 July. The head of the RAF was told of the drive for an endgame during a visit to the Paris air show this week. Air Chief Marshal Sir Stephen Dalton has refused to comment but he is among senior allied officers aware of sense of acute urgency in the Elysée Palace, with the mission now in its third month of bombing.

It is unclear whether President Sarkozy still hopes for a total ousting of Gaddafi, the demand of France, Britain and Libya's opposition administration, or is veering towards an end to hostilities with Gaddafi's future to be decided later, a course, diplomatic sources say, his Foreign Minister, Alain Juppe, favours.

But a senior UK officer said: "Sarkozy wants to make a big announcement on Bastille Day, after the parade, and that has become something of a constant theme. The French military are under real pressure on this and, so by proxy, are we. One can't conjure up victory, but there is a timeline to all this now."

British ministers have been claiming privately that there is now much better information on Gaddafi's "hiding places", with the inference that he will face an accurate air strike. A Downing Street spokesman insisted yesterday that military campaign would continue full steam ahead.

But David Cameron has been forced to speak out after British military chiefs warned of the strains imposed by combat in both Libya and Afghanistan. The government will today announce how much the campaign has cost, a figure believed to be £200 to £250m, although Chancellor George Osborne projected only "tens of millions of pounds" when the bombing started at the end of February.

Yesterday, on television, the head of the Army, General Sir Peter Wall, cautioned that withdrawal of UK combat troops in Helmand province by 2014 needs to be "conditions-based", a reminder that away from efforts to topple Gaddafi, British forces continue to face a bloody insurgency. Days ago, Admiral Sir Mark Stanhope, the head of the Navy and the RAF's chief of operations, Air Chief Marshal Sir Simon Bryant, highlighted the problem their respective services would face if the Libyan operation went on beyond September. An agitated Mr Cameron told reporters: "There are moments when I wake up in morning and read the newspapers and I think, 'You do the fighting, I'll do the talking'."