No Aussies affected in Mosul attack: PM

No Australian troops were affected by a low-grade chemical attack in western Mosul, Prime Minister Malcolm Turnbull has been advised.

"But Australian forces did provide assistance following the attack," he told ABC radio on Wednesday.

The ABC says the Pentagon has described the attack on an Iraqi unit that also contained Australian and US advisers as largely ineffective.

A US Defense official has told the ABC the foreign advisers were medically screen and showed no signs of exposure and have returned to duty.