Australia denied as "nonsense" Thursday claims in a British newspaper that it played an "integral" part in illegally detaining prisoners of war at a secret Iraqi desert jail in 2003.

The Guardian, citing a US military document, said an elite Australian squadron of 150 men was involved in the operation of a facility known as H1, a so-called black site, or secret prison hidden from the Red Cross.

The newspaper claimed a British special forces unit and the Australian Special Air Service (SAS) squadron "were an integral part of operations at H1. Both units were under US tactical control."

The Public Interest Advocacy Centre, a human rights organisation that has been investigating illegal detention in Iraq and Afghanistan, said the revelation cast doubt on Australia's compliance with international law.

But Alexander Downer, who was foreign minister at the time, dismissed the allegations.

"I think that's likely to be complete nonsense," he told the Australian Broadcasting Corporation.

"I don't think the SAS would have known anything about black sites at that time and certainly we didn't in the Australian government. But we did have protocols in place.

"If memory serves me well... we didn't actually detain prisoners ourselves but we handed them over to countries that -- and obviously to the Americans and the British in particular at that time -- signed up to international norms of treatment of prisoners in circumstances like that."

Current Defence Minister Stephen Smith said he had been advised there was nothing in the newspaper report.

"I've got no knowledge of these matters at all," he said.

"These were matters before the (current) government was elected so they were matters during the period of the previous government.

"Historically, successive Australian governments and the Australian Defence Force have prided ourselves on the fact that we have very high standards in this area."

Black sites became infamous after the Abu Ghraib scandal, where photographs showed that a US military unit had mistreated Iraqi prisoners there, severely damaging international opinion about the US-led war effort.