The foreign ministry's information office chief said "extremely angry" Arabs from Jordan, Egypt and Morocco had shown up at the Iraqi embassy in Damascus to sign up to fight the invading US and British forces.

"The Syrian government advised them not to go, because they are not qualified and it's dangerous for their life to go," Bussaina Shaaban told a press conference.

However, she made no mention of Syrians crossing the border.

Iraqi Vice President Taha Yassin Ramadan said last week that more than 6,000 Arab volunteers had reached Iraq.

US officers on the ground in Iraq also revealed they had found Egyptians, Jordanians, Saudis and Syrians fighting alongside Iraqi troops, using tactics including suicide bombings. Other reports have come in from Cairo to Stockholm of Arabs volunteering to join the battle.

Syria was recently accused by the United States of sending military supplies, including night-vision goggles, to support Iraq, and officials in Washington have warned Damascus would be held accountable.

The hostile rhetoric has raised speculation that Syria, as well as Iran, could be next on Washington's hit list. Britain has said US and British forces waging war on Iraq had no such plans.

SPACE.WIRE