Negotiations to resolve the standoff have been taking place at the runway, in Moscow, and on the telephone between the Russian and US presidents.

The deadlock has highlighted the dispute over Russia's role in the international peace keeping force for Kosovo, K-For.

Russia wants its own sector to control in Kosovo and its own independent chain of command.

Nato is refusing the Russian demands. It fears a Russian sector will become a magnet for Serbs and in effect lead to a partition of the province.

Perimeter tensions

Kate Adie reports: "The situation is delicate and not without tension"

British commanders have negotiated partial entry to the airport but have been blocked from taking total control by a contingent of 200 Russian troops.

The British soldiers have been parked near the airport perimeter. At some stages on Sunday they have been just yards from Yugoslav troops who have yet to withdraw from the city.

At times tempers have flared between Russian and Nato forces. One British officer, Captain Martin Gorwyn, accused the Russians of "deliberate foot-dragging".

Yards apart: Nato and Serbs

Russian armoured vehicles have blocked the road to refuse access to Nato troops but are allowing local traffic through.

Nato had planned for British troops to set up its headquarters at the airport.

A senior Nato officer admitted that the alliance has opened a temporary headquarters away from the airport.

Despite the standoff, Nato Supreme Commander General Wesley Clark has insisted the airport is not crucial and that K-For had never planned to use it for any deployment purposes.

Military settlement

But Nato leaders want the situation resolved and diplomatic talks have been taking place throughout Sunday.

Washington Correspondent Richard Lister: "Generals to decide"

Presidents Clinton and Yeltsin have spoken on the phone and agreed the matter should be settled by military commanders.

White House spokesman Mike Hammer said the two leaders had agreed Russian and Nato generals should meet "military to military and general to general".

He said: "We're looking to have Russian participation in K-For that is reflective of their important role.

"We would welcome, and would like to see, a meaningful deployment of Russian troops provided that it is within ... the chain of command that had been established."

He said that no timetable had been drawn up for finding a solution but added the presidents agreed to talk about the situation again on Monday.

British commanders have been talking to their Russian counterparts in Pristina to try to ease the tension on the ground in Kosovo.

Compromise deal

The American envoy, Strobe Talbott said earlier that he had been told Russia would send no more troops to Kosovo until an agreement had been reached.

Mr Talbott offered an American concession by allowing Russia a "zone of responsibility" in Kosovo.

It has been reported that details for the zone, which falls short of full control of a sector in Kosovo, are still being thrashed out.