Two rocket-propelled grenades were fired at the building.

One hit the side of the barracks and the other landed 50 metres away.

None of the soldiers were wounded and there are no reports of civilian injuries.

The Australian security detachment protects Australian diplomats and other officials.

In October, three members of the force were injured when the convoy they were escorting was attacked by a suicide car bomber.

In other violence, four men were hauled from their car by masked men in the northern Iraqi city of Mosul on Friday and killed, witnesses said, adding that at least one of them may have been a non-Iraqi.

In Ankara, the Turkish foreign ministry said several of its embassy guards on their way to Baghdad were killed Friday in an armed attack on a road in Mosul.

It did not specify how many guards died, but CNN Turk television put the number at four.

Mosul is northern Iraq’s largest city, and has been the scene of bloody attacks on Iraqi and US forces in recent months, leading to a fluctuating state of lawlessness.

Over 60 bodies have been found in Mosul, 370 kilometres north of the capital, since the beginning of December, many of them belonging to members of Iraqi security forces executed by insurgents.

Meanwhile, the United States has formally written off all of its $A5.4 billion Iraqi debt.

It has urged other nations to follow suit as a critical move for the country’s reconstruction.

US Secretary of State Colin Powell, Treasury Secretary John Snow and Iraqi Finance Minister Adil Abd Al-Mahdi have signed the accord formalising the US commitment made to the Paris Club of Iraqi creditors last month.

The group of 19 creditors agreed to cancel 80 per cent of the approximately $A53 billion in debt owed by the ousted regime of Saddam Hussein.

Washington went further and agreed to wipe out its entire share.