The UK prime minister, on a visit to Belgium for a series of meetings with military and political leaders, stressed the moral case for military action.

Mr Blair also gave an upbeat progress report about the success rate of Nato air raids, saying they had severely damaged the "killing machine" of Yugoslav President Slobodan Milosevic.

David Shukman reports on Tony Blair's effort to boost the Nato war of words

"I assure you of our determination to see this through to the end," he told a news conference at Nato headquarters in Mons.

He said that the international community had been horrified by the accounts of massacres and rapes told by the hundreds of thousands of refugees forced from their homes by gunpoint.

Only Nato can help the refugees get home Mr Blair says

"My generation never thought to see those scenes in Europe again, and our task is very simple and our will in seeing it through must be absolute and total," he said.

"I think there is a proper sense of moral outrage about what Milosevic has done that we should not shy away from and should feel proud to be feeling."

Mr Blair also insisted that the success of Nato's action was "the only chance" that the refugees had of returning home.

Air raid destruction

The prime minister said at least 13 different military targets had been hit by Nato raids on Monday night.

The vehicles destroyed included five tanks, four armoured personnel carriers and about 20 other military vehicles, he said.

A troop assembly area, a surface-to-surface missile system, ammunition depots, army headquarters, airfields, oil depots and refineries and "other parts of the Serb military machine" were also attacked.

Mr Blair detailed the losses to the Serbian air force and fuel depots and supply routes.

Earlier, Mr Blair delivered a personal message of support to Nato's commanders via a video link.

In a message beamed to officers across Europe, he said: "You are fighting a just war in a just cause.

"I'd simply like to say to all of you, to thank all of you, for the work you are doing - not just the military action but the extraordinary humanitarian effort as well.

"It's deeply appreciated by all of us."

Mr Blair is also due to visit the RAF Bruggen base in Germany to meet the crews of Tornado bombers, who are involved in Nato bombing of Serbia.

With the campaign soon to enter its fifth week, doubts continue to be expressed about whether the air-power strategy is working.

The prime minister will visit Tornado crews

This has combined with growing speculation mounting about the possibility of a ground-troops option.

Mr Blair has been amongst the strongest advocates of Nato's current approach. By travelling to Brussels, he is demonstrating strong support for the Alliance's military commanders and emphasising that solid backing remains throughout Nato for the current strategy.