"If President Milosevic will not make peace, we will limit his ability to make war," he said in a nationally televised address.

Mr Clinton said the military action had three goals:

• to demonstrate the seriousness of Nato's opposition to aggression

• to deter President Milosevic from further attacks on Kosovo Albanians

• to damage Serbia's capacity to wage war

As bombs exploded across Yugoslavia, Mr Clinton told America there was a "moral imperative" to end Serb attacks on Kosovo Albanians.

http://news.bbc.co.uk/hi/english/static/kosovo_fact_files/default.stm

"We act to protect thousands of innocent people in Kosovo from a mounting military offensive," he said.

"We act to prevent a wider war, to defuse a powder keg at the heart of Europe, that has exploded twice before in this century with catastrophic results."

Geography lesson

The president, using a pointer and a coloured map to show Americans where Kosovo is, gave the nation a crash course in European history.

He warned that US forces faced grave risks but indicated the assault would not involve any ground troops.

"I do not intend to put our troops into Kosovo to fight a war," he added.

'Full-blown crisis'

Speaking earlier, Mr Clinton stressed that Nato laid the blame fully on President Milosevic who had ''chosen aggression over peace".

Mr Clinton: No ground war

''As I speak, more Serb forces are moving into Kosovo and more people are fleeing their homes."

Some 60,000 ethnic Albanians had been driven from their homes in the last five weeks, he said, and 250,000 altogether.

A chance for peace

''After two world wars and a cold war, we and our allies have a chance to leave our children with a Europe that is free, peaceful and stable,'' the president said.

"But we must act now to do that, because if the Balkans once again become a place of brutal killing and massive refugee flights, it will be impossible to achieve.

''I have concluded that the dangers of acting now are clearly outweighed by the risks of failing to act,'' he added.

Mr Clinton said there was a danger that many more innocent people would die, and neighbouring nations would become destabilised if the allies delayed action.

The US must stand with its Nato allies ''against ethnic violence and atrocity", he added.