UN tells Croats to withdraw after two French soldiers die: Marcus Tanner in Belgrade reports on fighting in both Krajina and Bosnia as the Geneva peace talks resume

SERBIA'S armed forces were put on the alert yesterday after Croatian forces captured the vital airport at Zemunik from Serbs. Two French United Nations peace-keepers were killed by shells, a UN spokesman said.

Fighting also increased sharply between Serbs and Muslims in Bosnia, spreading along the whole length of the river Drina which divides Bosnia and Serbia. Serbs claimed success in pushing back mostly Muslim government forces. Battles were reported to be raging along a 100km (62-mile) stretch of eastern Bosnia from Rudo to Zvornik.

The UN Security Council last night demanded the withdrawal of the Croatian troops. In a unanimous resolution, it condemned attacks by these troops against the UN Protection Force and demanded their immediate cessation.

In Belgrade, the Supreme Defence Council, attended by Serbia's President Slobodan Milosevic, said Croatia's incursions into the Serbian-held Krajina region, on top of attacks by Bosnian Muslims, had 'undoubtedly threatened the security of Yugoslavia'.

But Admiral Sveto Letica, a Croatian navy commander, said Croatian forces were fighting to push the Serbs back from Croatia's Adriatic coast to a new ceasefire line 20km (12 miles) south-east of the previous one. 'Serbs should withdraw south-east of that line and the Croatians will not fire any more,' he said.

In spite of the fighting, Bosnia's warring Muslim, Serbian and Croatian leaders resumed peace talks in Geneva. The talks were broken off last week when fighting broke out in Croatia, ending a fragile year-long truce.

In Geneva, the president of the rump Yugoslavia, Dobrica Cosic, demanded the UN force the Croats to withdraw to the previous ceasefire line, accusing Croatia of 'ripping up the Vance plan'.

Russia branded Croatian attacks on Serbian targets as unacceptable. The deputy Foreign Minister, Vitaly Churkin, said: 'If the Croatian side does not cease military actions against Serbs, Russia will move a resolution to introduce international sanctions against Croatia.'

In Britain, unease among Tory backbenchers resurfaced yesterday as MPs digested the implications of the Prime Minister's refusal at the weekend to rule out a possible peace-keeping role for British troops in Bosnia.

As heavyweight Tories renewed warnings about Britain becoming 'sucked in' to the conflict, concerns - though not so vociferously articulated - also came from Labour. George Robertson, Labour's front-bench spokesman on European affairs, said: 'There is some reluctance on our side too. There is a fairly uneasy feeling about being dragged into this one.'

RAF Jaguar strike aircraft standing by to go to Bosnia are being fitted with extra weapons and equipment, according to the magazine Flight International.

The aircraft, at RAF Coltishall in Norfolk, are being upgraded to carry Sidewinder missiles, as in the Gulf war, and may be sent to northern Italy if the threat to British forces in Bosnia increases, the magazine said.

The Ministry of Defence refused to comment.

(Photograph omitted)