The Foreign Minister, Alexander Downer, and the trade minister, Mark Vaile, are due to deliver written statements to the Cole inquiry today.
The statements about whether they knew of almost $300 million in Australian Wheat Board kickbacks to the former Iraqi dictatorship of Saddam Hussein are expected to stay confidential for now.
Mr Downer has already said he and Mr Vaile were not aware of serious concerns about the wheat exporter until they received a confidential minute in 2004.
He has declined to elaborate on his evidence.
He says Commissioner Terence Cole should be left to make his report about the deals before any further debate.