New documents released by the U.S Justice Department say Attorney General Alberto Gonzales attended a meeting last November that discussed the eventual firings of eight U.S. attorneys.
The new documents contradict earlier claims by Gonzales that he did not directly participate in any discussions about the dismissals.
Spokespersons for the Justice Department say Gonzales and other senior officials focused on finalizing the plan to dismiss the attorneys, but did not specifically discuss which attorneys would be let go.
The documents were released hours after Kyle Sampson, Gonzales' former chief-of-staff, agreed to testify next Thursday before the U.S. Senate Judiciary Committee about the firings. Sampson resigned his post last week in the wake of the controversy over the dismissals.
Critics of the firings say they were politically motivated, that senior White House officials were deeply involved, and that top Justice Department officials misled members of Congress about the reasons for the dismissals. Some lawmakers are calling on Gonzales to resign over the controversy.
On Wednesday, a House Judiciary subcommittee also voted to authorize subpoenas to compel President Bush's aides to testify, in public and under oath, with a written transcript. The Senate Judiciary Committee took a similar action on Thursday.
Democratic leaders have rejected the president's offer to let congressional investigators privately interview his chief political advisor, Karl Rove, and former counsel Harriet Miers, without taking an oath and with no transcripts of the meeting.
White House spokesman Tony Snow suggests Democrats want to stage a show trial for purely partisan reasons.
Some information for this report was provided by AP and Reuters.