Briefing reporters less than an hour before the 0100 GMT US deadline for war, ADF spokesman Brigadier Mike Hannan said Special Air Servicescommandos were preparing for the attack.

"The special forces task group by this stage would have received their orders through the chain of command," he said.

"And they will be transitioning from their acclimatisation and general training programs and they'll be undertaking preparation specific to the operations ahead," he said.

Hannan did not say when war might commence.

But Foreign Minister Alexander Downer said he expected the conflict to start soon after the 0100 GMT deadline set by US President George W. Bush for Iraqi leader Saddam Hussein to quit his country or face attack.

"The deadline is about to arrive at midday today Australian time and I think we can expect information about military action at any time now," Downer said.

"Of course this is a matter that's in the hands of the commanders on the ground," he added.

Australia has deployed about 2,000 troops to the Gulf, including about 150 SAS commandos for the war, despite strong public opposition at home to participation in the conflict in the absence of explicit UN approval.

The Australians are a tiny part of a massive US-British deployment of some 280,000 troops for the invasion.

WAR.WIRE