The independent senator, who is a former soldier, asked the defence minister at Senate estimates on Wednesday whether she'd support a push to excuse Australian soldiers from elements of international law.

"Does the minister agree," Lambie said, "with my call for her government to draft, support, and place a law before this parliament which pre-emptively pardons and absolves any serving or former ADF member accused of war crimes or breaches of the Geneva convention during their service in the fight against the Taliban and other Islamic extremists in the Middle East?"

Lambie went on to explain her reasoning, suggesting Islamic extremists "do not follow Geneva conventions or any rules of war", and said the parliament could show its "extraordinary debt of gratitude" to Australian soldiers by exempting them from international law.

It was revealed this week that Australian special forces were part of the Iraqi military's offensive to retake the city of Mosul from ISIS.

Last week Australian commando sergeant Kevin Frost told ABC News he was ready to be "punished" for his role in an alleged unlawful execution in Afghanistan.

The ABC News story revealed the Inspector General of the Australian Defence Force was conducting a "secretive and sweeping inquiry" into the conduct of Australian commandos in Afghanistan, including into possible breaches of Geneva conventions.

Defence minister Marise Payne said the government would not entertain Lambie's idea for pre-exemptions for Australians soldiers.

"Your proposition is not one I’d be agreeing with, in the context of this estimates hearing this morning," said Payne.