The Pentagon has acknowledged that Vice-President Dick Cheney's chief of staff and other political appointees helped make the controversial decision on a $1.8 million contract for the postwar recovery of Iraq's oil sector.
The decision to award the contract to the energy giant Halliburton overruled recommendations of an army lawyer. Eventually it resulted in the awarding of a much larger $US7 billion ($A10 billion) no-bid contract to Halliburton. Mr Cheney ran Halliburton for five years before he was nominated for vice-president.
Democrat congressman Henry Waxman said the new details about Halliburton and Mr Cheney's office were disclosed last week in a Pentagon briefing to Democratic and Republican staff from the Government Reform Committee.
Mr Waxman said the briefing raised new questions about whether the Vice-President played any role in decisions to give what became billions of dollars' worth of Government business to Halliburton without going to tender.
Mr Cheney, who was chief executive of the Houston-based oil services company from 1995 to 2000, has repeatedly denied that he or his office influenced decisions to give contracts to Halliburton.
In a letter to Mr Cheney on Sunday, Mr Waxman said the circumstances "appear to contradict your assertions that you were not informed about the Halliburton contracts".
"They also seem to contradict the Administration's repeated assertions that political appointees were not involved in the award of contracts to Halliburton," he wrote.
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