Sergio Vieira de Mello said his humanitarian mission had gathered enough evidence to confirm there had been attempts to displace a "shocking" number of civilians.

"In one word, it is pretty revolting," he told reporters following the three-day trip.

Speaking in Montenegro, he said he had travelled extensively in Kosovo, although the Serbs had prevented his party from visiting some areas.

Sergio Vieira de Mello: Reality in Kosovo was worse than I thought

He said what they did see was enough for a "picture of what went on'' and that the scale of the crisis was "gigantic".

''Everything indicates that there is an attempt to displace, ethnically cleanse, Kosovo," Mr de Mello added.

Yugoslav denial

The Yugoslav ambassador to the UN, Vladislav Jovanovic, denied ethnic cleansing was official policy, but pointed out that a state of war existed in Kosovo with both sides involved in hostilities.

Mr de Mello's first-hand account backs up the individual testimonies of thousands of refugees who have fled the province over the past two months.

He also said there were "possibly hundreds of thousands" of Kosovo Albanians displaced within Kosovo who were "in a desperate need of assistance''.

"We have seen many of them in the last three days, receiving very little support. Certainly nothing from the international community," he added.

Mr de Mello is scheduled to have discussions with Yugoslav government officials in Belgrade on Wednesday.