"My fellow citizens, at this hour, American and coalition forces are in the early stages of military operations to disarm Iraq, to free its people and to defend the world from grave danger," he said in a televised address.

"On my orders, coalition forces have begun striking selected targets of military importance to undermine Saddam Hussein's ability to wage war," he said in the hurriedly announced speech.

"These are opening stages of what will be a broad and concerted campaign," he promised.

The attacks started early Thursday, with warplanes bombarding the country shortly after a US deadline passed for President Saddam Hussein to leave the country.

An AFP correspondent in Baghdad said anti-aircraft batteries were heard firing at warplanes strafing the Iraqi capital, at the beginning of a military conflict that has shaken the world community.

"The opening stages of the disarmament of the Iraqi regime have begun," White House spokesman Ari Fleischer said in Washington.

The US military had earlier refused all comment on the movement of its forces after 0100 GMT, the deadline laid down by Bush for Saddam and his sons to quit the country or face the world's mightiest military.

More than 250,000 US and British ground troops, backed up by a massive naval armada as well as hundreds of warplanes at the ready in the Gulf, are massed on the outskirts of Iraq but there was no immediate word on their movements.

Bush and his closest ally on Iraq, British Prime Minister Tony Blair, say Saddam is harboring weapons of mass destruction and have vowed to see him ousted from the country he has ruled with an iron grip since 1979.

But Saddam and the Iraqi leadership insist that US troops will meet their death in the desert sands of Iraq, which is facing its second US-led war since 1991, when US forces led a coalition to eject Saddam's troops from Kuwait.

In a televised address Monday that was watched around the world, Bush said the time had come to push Saddam out of power, and gave him 48 hours to flee or face an invasion from the world's mightiest army.

But the Iraqi leader rejected the ultimatum as "despicable" and repeatedly vowed that he would choose to die in his homeland rather than surrender under US pressure.

The prospect of a US-led war has shattered the world community and strained relations between Washington and longtime allies such as France, while drawing warnings from Islamic militants of attacks on US interests worldwide.

UN Secretary General Kofi Annan even took the unusual step of criticizing the United States, amid what has been widely seen as a US diplomatic failure to rally international support for an attack to topple Saddam.

Bush has linked Iraq to an "axis of evil" that includes next-door Iran as well as North Korea, and says Saddam is a tyrant who must be ousted as part of Washington's campaign against terrorism.

But Saddam has vowed to resist and the Iraqi parliament on Wednesday gave him its unanimous support, with MPs pledging to die to defend him.

Saddam on Wednesday said Iraq no longer had weapons of mass destruction, which Washington originally insisted was the source of its concern over Baghdad after the September 11 attacks.

UN arms inspectors, tasked under UN Security Council resolutions to verify that Baghdad harbors no chemical, biological or nuclear weapons, were pulled out of the country in the hours before Bush's deadline.

But Washington has since said that eliminating such weapons is not enough, and that Saddam and the Iraqi leadership must go.

(China Daily March 20, 2003)