Reiterating its earlier finding of no links between Iraq and al-Qaida, the 10-member bipartisan panel investigating the 2001 attacks on New York and Washington said that it had access to the same information the vice-president has seen.
"The 9/11 Commission believes it has access to the same information the vice president has seen regarding contacts between al-Qaida and Iraq prior to the 9/11 attacks," the commission said in a statement.
The vice president's office had no immediate comment on the commission statement.
Last year's US-led invasion and occupation of Iraq was sold to the public on the assertions that Iraq had weapons of mass destruction and could supply them to al-Qaida.
No such links or weapons have emerged from the war-ravaged oil-rich nation.
Although the September 11 Commission said in a staff report last month that there was no evidence of a collaborative relationship between the two sides, Cheney continued to maintain that long-standing links existed.