According to the Cypriot envoy and former President Spyros Kyprianou, a mission to win the release of the three men failed because of intensified Nato bombing.

He said that attacks occurred in the Belgrade area and elsewhere within hours of his arrival on Thursday in the Yugoslav capital.

"It was expected ... that during my stay at least some respect should have been shown and some understanding until I had finished my consultations," he said.

Washington has been swift in saying the failure of Mr Kyprianou's mission is not a surprise.

Bomb damage inspections

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Mr Kyprianou met President Slobodan Milosevic for 90 minutes on Friday.

The Yugoslavian government first invited him to inspect damage caused by a Nato air raid in a residential area of the town of Aleksinac.

Kyprianou: Met Mr Milosevic

Mr Kyprianou expressed concern at the extent of the damage he saw.

"I am not a military expert but I have seen things that shocked me," he said.

A BBC correspondent in Belgrade said the authorities were keen to exploit the propaganda value of Nato's error which, according to the most recent figures from the official state news agency, caused the deaths of 18 civilians.

Propaganda value

before the meeting, Mr Kyprianou's aides said they were optimistic about securing the freedom of the three Americans.

But one of Yugoslavia's Deputy Prime Ministers, the hardliner Vojislav Seselj, said on Thursday there was no question of the prisoners being allowed to return home.

The soldiers - Andrew Ramirez, 24, Christopher Stone, 25, of Michigan and Steven Gonzales, 24, of Texas, were captured by Serbian security forces on the border between Yugoslavia and Macedonia on 31 March.