But behind the scenes, there are growing worries that the plan is not working. Despite the Defence Secretary's assertion yesterday that the bombing has "seriously rattled" Slobodan Milosevic, driving him to make his peace offer, there is growing fear of a strategic stalemate with no military victory in sight. Six days of intensive bombardment have failed to take out the Serb anti-aircraft defences, with damage estimated at being only "minimal to moderate", say military sources. The hit rate is low, and the US Air Force is down to its last hundred cruise missiles.
The new programme of strikes will extend north of the 44th parallel, allowing allied aircraft to attack political and military targets in Belgrade, such as the interior ministry. But the US had indicated yesterday that such attacks were due, diluting the effect of the move. "The interior ministry will now be empty," said one official in Washington. And the extension does not go as far as the US and Britain had hoped because some Nato powers, particularly Italy, are nervous about the attacks.
If the extension does not yield results, it is unclear whether Nato has anything more up its sleeve.
Despite some pressure in the US for ground forces, there is no sign of a change of heart in the White House or Pentagon.
Some officials have talked of setting up a demilitarised zone on the Yugoslav borders with allied aircraft patrolling the skies.
In London yesterday the chief of the defence staff, General Sir Charles Guthrie, admitted the operation had not gone as far forward as hoped. He said: "It could be a long haul. It will be dangerous. He [Milosevic] may, we hope, see sense quickly but we have to steel ourselves for a long campaign if that is what is required."
General Guthrie said Nato forces on Tuesday struck targets throughout Yugoslavia, concentrating on Kosovo. For the first time, RAF Harriers had flown daylight search-and- destroy missions for tanks and artillery used by the Serbs against villages and farms. But the weather had been against them and the six Harrier were again prevented from carrying out attacks. Cruise missiles were successfully launchedagainst "important targets".
In the first five days of the campaign, about 90 attacks were made against at least 70 "individual sites". Eight airfields had been targeted and seven aircraft destroyed in addition to four MiG-29s and a MiG-21 shot down while trying to intercept Nato planes. There have been 16 attacks on radar and early-warning systems and 16 attacks on surface-to-air missile sites. Twelve of the further 15 air defence facilities have also been struck.
The broadening of the range of targets and extension of attacks will take place alongside a significant increase in low flying. This will inevitably mean a higher risk to the pilots.
Five B-1 bombers are to be stationed at RAF Fairford, in Gloucestershire, to join 13 B-52s. The Defence Secretary, George Robertson, said: "Nato planes are able very easily to bomb despite the weather, but cannot do so with the accuracy that we believe is absolutely critical.
"Milosevic may ignore the rules of humanitarian law; international law is meaningless to him as the violence we are seeing proves, but we constrain ourselves in acting in a humane manner and therefore we will not take risks with civilian casualties simply to drop bombs on what we think might be military targets." Nato aircraft would now increase the damage to Mr Milosevic's war machine, including tank and troop concentrations, he said.
"We know where they have dispersed to and we know where they are hiding. They are not going to escape."
President Milosevic's offer to try to end the Nato bombing showed he was "seriously rattled" by the bombing. The offer was the "first crack in Milosevic's wall of obstinacy" but showed the Yugoslav leader had miscalculated again. "Milosevic's offer can be summed up in this way - Nato stops bombing, he only slows the killing. There was no offer of a ceasefire, no offer to stop violence and crimes against humanity and there was no offer to pull out troops to the level he agreed last October. This was no peace move. It was Milosevic blinking in the face of the blows inflicted on his military regime."
General Guthrie said there was increasing intelligence showing a close relationship between Mr Milosevic and the Iraqi leader Saddam Hussein.Reuse content