Nato jets ready to strike back against Serbs: Attacks on artillery await approval of UN chief and deployment of controllers on the ground

AS SERBIAN forces step up their drive to conquer the western part of Sarajevo, air strikes against their artillery positions looked increasingly likely yesterday. The US held intensive consultations with its allies, and the UN Secretary-General, Boutros Boutros-Ghali, said Nato aircraft should start providing air support for UN troops in Bosnia by early next week.

United Nations diplomatic sources said the 'momentum is building' for the strikes and they could come at any time. In Washington, President Bill Clinton said the US is now ready to provide air support, after the recent shellings of France's UN contingent in Sarajevo.

'We are ready to go if asked,' Mr Clinton said just before a meeting with national security advisers. In recent days, the US has sent extra F-18s, A-10s and other ground-attack jets to its bases at Aviano in north-eastern Italy and Brindisi in the south. The aircraft carrier USS Theodore Roosevelt is steaming to within range of Bosnia.

Mr Boutros-Ghali, who must give the green light for any air strikes, said: 'Everything will be finished by Monday or Tuesday . . . I hope we will be able to find a definitive solution on Monday or Tuesday.'

The US, Mr Clinton declared yesterday, 'has always had the public and private position - we made it very clear - that if the UN operation in Bosnia was under attack, we would be prepared to defend them.' No formal request from France, channelled through the UN Secretary-General, has yet reached Washington, he said. But the President's remarks show the US response is no longer in doubt.

The US, Britain, Canada, Spain and Russia committed themselves last May in UN Security Council Resolution 836 to protect UN forces in Bosnia with air power, if necessary. The planes, including a squadron of 12 British Jaguar ground-attack aircraft based in Italy, are drawn from Nato forces.

The British air forces in the area also include Harrier jump-jets on board the aircraft carrier Ark Royal, which can perform ground-attack roles, and land-based Tornado F-3 fighters, which have been helping to enforce the 'no-fly zone' over Bosnia - until now the only allied air intervention in the war.

There are increasing signs of a broader impending shift in US policy in Bosnia.

Only a week ago, Warren Christopher, the Secretary of State, had seemed to wash America's hands of Bosnia's plight, insisting the US already was 'doing all it can consistent with our national interest'. But yesterday Mr Clinton declared himself 'very upset' by the Serbian shelling of besieged Sarajevo, while Vice-President Al Gore - a strong advocate of intervention - told the Washington Post that 'a number of elements' in US policy were under 'intensive review'.

Any final decision by the UN also depends on when its forces in Bosnia have completed the deployment of 20 teams of the forward-based air controllers, or FACs, who would guide the aircraft to their targets.

These teams are needed because most of the targets are expected to be in populated areas. Thus far, eleven of the teams - four British, five French and two Canadian - are in place in Bosnia and four Danish teams have been deployed in Croatia. Full deployment of the air controllers could not be completed until early next month, but that would not prevent some strikes being made beforehand, UN sources said.

Deeply conscious of the possibility of 'collateral damage' to friendly forces and the Bosnian population, the UN is constructing an elaborate network of forward air controllers to assist low- flying attack aircraft to send their laser-guided rockets on to the targets. Before an attack the FACs, who could be literally in a field somewhere, would radio the position of the target to a control vehicle, which would send it to a co-ordination centre, which would inform the UN force commander, who would produce 'air tasking messages' for the pilots.

The probable method of execution of the UN Secretary-General's order will be to give the Serbian forces a specific warning to remove artillery that had shot at UN forces by a certain time, or it will be bombed. Following the first strikes, no further authorisation by Mr Boutros-Ghali would be required.

Bosnians told to 'face reality' 11