The claims emerged in the sensational finale of a nine-month probe into whether Australian wheat exporter AWB illegally channelled 220 million US dollars to the regime of Saddam, who is on trial in Iraq for the genocide of 182,000 people in a 1987-88 campaign against the Kurds.

In a last-minute twist, a lawyer for the probe revealed that the wheat exporting monopoly could face terrorism-related charges if it knowingly supplied cash that could have funded human rights atrocities.

An internal document appeared to suggest that executives of AWB, which has taken a severe battering at the inquiry, knew the Iraqis wanted foreign currency in 2001 to build 2,000 concrete burial bunkers.

"The bunkers will have cement walls and floors so they are actually designed for burying the Kurds," an email from AWB executive Daryl Borlase to several other AWB staff said.

"Under the cement?? They intend to build them with fumigation capability so the mind boggles as to whether they are fumigating insects or any other pest that pisses them off," read the email, written in light-hearted style.

"On a serious note they will have cement flooring," it continued.

The inquiry has heard that when the email was written, AWB was funnelling huge bribes to Saddam's government in the form of so-called trucking fees paid to a Jordanian transport firm, Alia, part-owned by the dictator's regime.

The moves were in defiance of UN sanctions in force against Iraq at the time.

Lawyer John Agius said that under its terms of reference, the inquiry must consider "whether or not it might be said that AWB and others might have committed an offence under the terrorism offences in the (Australian) criminal code."

Anyone guilty of providing or collecting funds to "facilitate a terrorist act and other initiatives" could face life imprisonment.

Agius questioned AWB's former managing director Andrew Lindberg about the email, asking if the firm's staff knew of the atrocities that Saddam's government was capable of while it was passing it kickbacks.

"Would you agree ... there were personnel within AWB (who knew) what the Iraqi regime was capable of doing?" Agius asked.

A clearly uneasy Lindberg conceded the interpretation could be made but said he hoped the email comments had not been meant "in a serious way."

The former managing director also admitted that he knew that United Nations sanctions against Iraq were designed to prevent the regime from accessing foreign currency to buy guns or fund atrocities.

Agius said media reports about Saddam's alleged weapons of mass destruction and human rights abuses against sections of Iraq's population, including the minority Kurdish population, abounded at the time the email was written.

Inquiry head Terence Cole -- who had to wage court battles to win access to internal AWB documents showing how the kickback scheme worked, hundreds of which were only produced this week -- said the firm's Iraq involvement had been a "disaster."

"Mr Lindberg, it does appear that large amounts of money did go from AWB to Iraq through Alia, and you've said to me that it happened and it shouldn't have happened."

"It's obviously been a disaster for AWB and, no doubt, for you personally," he told the witness, who broke down in tears and had to be escorted off the stand.

AWB lost a lengthy court battle to keep its documents under wraps by arguing they were subject to legal privilege, and only produced hundreds of volumes of papers this week.

A Federal Court judge who threw out the company's case this month said AWB deliberately and dishonestly set out to defraud the United Nations through its improper dealings with Iraq.

There has been keen interest in whether Prime Minister John Howard's conservative government knew of the kickbacks before it joined the US-led invasion of Iraq in 2003 that toppled Saddam.

Howard -- a key supporter of US President George W. Bush's 2003 invasion -- and two senior ministers have appeared before the inquiry and strongly denied knowing anything about the bribes.

Cole is due to hand down his findings on November 24.