Eight floors underground, in a Ministry of Defence nuclear bunker, Britain chooses the targets Nato can attack.

The bunker lies 100ft below street level in Whitehall, London. Meetings are dominated by the crisis in Kosovo.

The men who run the UK's armed forces descend into the cramped and secret corridors every day, as they have done since the start of the Nato campaign.

The BBC's David Shukman: "I was allowed into the bunker where the msot sensitive plans are laid"

Every day the intelligence on potential targets is reviewed around the meeting table.

But the air campaign is not working as quickly as they had hoped it would. The disaster of the attack on the Chinese embassy makes the situation worse.

George Robertson arrives at the latest meeting

The fact that it went so wrong and led to the bombing of a neutral embassy is a source of extreme concern.

This is ultimately a political campaign, and blunders count, as Britain's diplomats in China have found out, following violent protests in Beijing.

Sources at the headquarters running British forces in the Balkans say the targets are pinpointed with great care. The view in the war room at Northwood, Middlesex, is that Nato's record in the campaign has been good.

The entrance to the bunker is closely guarded

But any decision to adjust the military campaign would be taken back in London, deep below the Ministry of Defence.

Winning in Kosovo takes more than the brute force of missiles and this reinforced concrete, however. It is also a question of Nato not making mistakes.

But as the bombing intensifies, so do the risks, and the people in charge know it.