Nato jets would be ready in minutes

NATO jets would be ready to attack Bosnian Serb positions within minutes of a decision to enforce any ultimatum. Based in Italy, the jets are most likely to be called in if the Serbian forces fail to meet a demand that they move their heavy weapons - including 120mm mortars of the type used in the Sarajevo market massacre - to at least 20km (12 miles) away from the Bosnian capital.

The pilots of the Nato aircraft equipped to attack ground targets are already familiar with the areas they may have to raid - they have carried out patrols over Bosnia for months. These patrols are so frequent that a decision to call in an air strike might involve jets already over the area rather than having to scramble aircraft from Italy.

On the ground, there are some 40 Nato tactical air control parties ready to direct attacks. These parties would not only select the targets, they would also determine which aircraft and armaments should be used.

The American A-10 tankbusters - which are armed with 30mm cannon that fire depleted uranium shells - would be the most likely to be used against the few Bosnian Serb tanks.

Laser-guided bombs would be used against artillery positions, ammunition dumps and other slightly 'softer' targets. Cluster bombs - which scatter bomblets over a wide area - are very unlikely to be used because of the risk to civilians and the fact that about 10 per cent of their bomblets tend not to explode.

The Serbian guns are currently deployed about 6km from the centre of Sarajevo. The best known artillery positions are at Vogosco, north-west of Sarajevo, at Rajlovac, roughly west, and Stup airport.

But there are other artillery positions at the same distance from the centre, ringing the entire Bosnian capital. The positions are prepared and dug-in, and the Serbs periodically move the guns from one to the other.

The most dangerous artillery pieces are Russian-designed 122mm and 152mm D-30s and

D-20s, which have ranges of 17km and 24km respectively. However, the 120mm mortars, with a range of up to 9km, would be more difficult to find. Artillery is the most lethal weapon in war: typically, it accounts for 50 to 75 per cent of all casualties.

Serbian reprisals against Nato air attacks could include: stopping all aid (70 per cent of aid reaching central Bosnia comes through Serb territory); kid napping or murdering aid workers, UN personnel and other foreigners; artillery attacks on UN bases, most of which are within range of Serb positions; and, possibly, attacks by Serbian submarines on foreign shipping. The presence of an anti-submarine, Type-22 frigate, HMS Coventry, in the Adriatic suggests that Western navies are aware of this threat.