Full alert as jets mobilise for Serbia as

NATO GEARED up to attack Serbia yesterday if peace talks over Kosovo fail, sending another 51 aircraft to Europe in advance of air strikes.

British embassy staff in the Serbian capital, Belgrade,began preparing to leave after the Foreign Office told non-essential staff to quit the country.

In Washington, the State Department said United States embassy personnel in Serbia would also be evacuated.

With the deadline looming, the British and French foreign ministers appealed directly to the Serbian public to accept the peace accord. Any decisionwould have "far-reaching consequences for you, your country and the whole of Europe", the Foreign Secretary, Robin Cook, and his French counterpart, Hubert Vedrine, said in a joint statement.

The US said it had ordered the deployment of aircraft, including 12 F117 Nighthawk stealth fighters, "to assure that Nato has the capability to conduct operations, should that prove necessary".

In the Macedonian capital Skopje, Nato's secretary-general, Javier Solana, warned that the alliance was ready to strike immediately if the deadline for a peace deal on Kosovo of noon tomorrow is not reached. "It would be very soon," he told a press conference, "if an agreement is not reached, if the negotiations fail, Nato knows very well what to do." As negotiations on Kosovo's future dragged on at Rambouillet in France the Nato threat appeared intended to boost the talks rather than signal an imminent attack.

Representatives of Kosovo's Albanian majority are demanding a referendum on independence from Serbia, while the Serbs are resisting demands from the big powers for a 30,000 Nato peace-keeping force to be deployed in the province.

Serbia's President Milan Milutinovic was due to return to the talks yesterday, giving rise to hopes that progress might still be possible. The US peace envoy, Christopher Hill, visited Belgrade on Tuesday to inject some energy into the process. Nato's ruling North Atlantic Council meets today to discuss the looming crisis. Nato issued an activation order for its forces last year, which is still in action. This allows Mr Solana to press the button whenever he wants, though in practice any decision would need the agreement of Nato's 16 members, in particular the US.

Despite the order for British diplomats to leave Serbia there was no sign yesterday of a plan to evacuate the 1,200 monitors in the country from the Organisation for Security and Co-operation in Europe.

There is already a French-led extraction force in Macedonia to help the monitors if necessary. Britain, Italy and France will also provide aircraft if strikes happen. Operation Noble Anvil, as the Nato action is designated, would involve hundreds of aircraft, the aircraft carrier USS Enterprise, B-52 and B-2 bombers.

If the alliance does launch strikes, it risks a confrontation with Moscow. The Russian President, Boris Yeltsin, said yesterday that he had told the Americans he would not permit air strikes on Russia's Serb ally. "I conveyed to Clinton my view, both by phone and by letter, that this will not work," he said. The US, however, said President Bill Clinton and President Yeltsin had not spoken.