The Foreign Secretary proposed during a full-day debate that the administration of Kosovo would have to be placed in the hands of international bodies like the United Nations and the European Union. But amid the toughening of Nato's military action, the Government faced mounting disquiet by backbenchers over its failure to seek Parliament's endorsement of the strikes with a vote.
Opening the debate, Mr Cook said the task of reconstruction, both of the shattered villages and of a democratic society within Kosovo, would take the combined efforts of an international protectorate.
"It would be our preference that a mandate should be provided by a UN Security Council resolution setting up an international administration for Kosovo. I believe it will not be possible to persuade the refugees to return to their homes without a credible military presence."
However, Foreign Office sources said the plans still needed to be discussed with the other Nato member states.
Mr Cook went on to warn that the continent was witnessing the "largest forced deportation in Europe since the time of Stalin or Hitler", under a planned assault by Belgrade.
He will today hand over a dossier of material "on multiple atrocities" and ethnic cleansing from the past three weeks to the chief prosecutor of the International War Crimes Tribunal.
Tony Benn, Labour MP for Chesterfield and leading opponent of the air strikes, argued that the Government's failure to seek Parliament's endorsement reduced MPs to the position "of a sort of press conference where we listen to ministers but have no opportunity to register our views or votes".
Kenneth Clarke, the former Chancellor, asked if the proposal of international administration for Kosovo was the "settled policy" of the Government and if it had been agreed by all the allies and with the neighbouring states.
Mr Cook replied: "It is going to have to be a much more hands-on operation than we envisaged at Rambouillet in the wake of the last four weeks. Yes, that is the view of the Government. It is a view in which we had close discussion with our major allies and I believe it is one ... which is widely shared among our allies."
Michael Howard, the shadow Foreign Secretary, pledged his party's continuing support for the action, adding that the Serbs' campaign of ethnic cleansing was the "most dire return to the dreadful reality" of the Second World War.
But while he would be the "last person to minimise the impact of the Nato campaign" it was time to face the "deeply unpalatable" fact that the bombing had not stopped the ethnic cleansing. It was time to reconsider how Nato could achieve its objectives, as it was clear from the "substantial reinforcements" now being made that the Alliance's original assessment had been "too optimistic".
Menzies Campbell, for the Liberal Democrats, said there were both "moral and pragmatic" reasons for stopping Serbia's "flagrant abuse of humanitarian standards".
"I believe that these objectives which we have set out can be attained but it will not be easy... the threat and indeed the use of ground forces will be an essential component in the achievement of any settlement," he said.
He added: "But if we are to ask our young men and increasingly our young women to risk their lives in the furtherance of political objectives, then surely they ought to know that they have had the endorsement of the House of Commons."
Gwyneth Dunwoody, Labour MP for Crewe and Nantwich, said it was "extremely difficult" on occasions for MPs to express unease about the way the situation was developing without that being construed as undermining the efforts of Britain's forces or their support of government.
"I will certainly find it difficult to support the commitment of ground troops if they go in to fight their way into a province which, frankly, is not only geographically extremely difficult for this kind of war, but also against very committed and certainly very tough opponents."Reuse content