But the White House again refused to supply information to Congress about the prosecutors, who lost their jobs in what Bush opponents say were politically motivated firings, the Washington Post reported.
White House resistance, Senator Patrick Leahy, the Democratic chair of the Judiciary Committee, said on Sunday he expected former Bush aide Sara Taylor to respond to a subpoena and testify before the committee on Wednesday.
Ex-political director Taylor has been called to hand over documents and testify in the drama over the firings of federal prosecutors, which has lawmakers from both sides of the aisle demanding the dismissal of Attorney General Alberto Gonzales.
"So far, the White House has not given us a single piece of paper. They've not given us a single witness. I think it's time for the stonewalling to stop," Leahy told CNN.
Lawmakers had asked for a justification for Bush's decision to defy congressional subpoenas over the dismissal of the nine prosecutors, and they want answers by Monday.
But the White House has decided not to provide any more information, the Post reported.
Taylor apparently is willing to testify, but is being blocked by the White House. Her lawyer has called on both sides to resolve the issue.
The fight is leading to "a monumental clash between the executive and legislative branches of government," said her lawyer, Neil Eggleston.
"This clash may ultimately be resolved by the judicial branch."
Frustrated Democrats have been stymied by Bush's resistance to various congressional investigations -- from probes on wiretaps without warrants to the firings of federal prosecutors.
Bush's lawyers have invoked "executive privilege" to rebuff subpoenas issued by the Senate and House of Representatives judiciary committees, targeting ex-White House counseland Taylor.
Executive privilege is a legal doctrine which argues the president can decline to produce documents and testimony demanded by another branch of government, if he deems it is vital that they remain confidential.
As lawmakers attempt to probe whether there was any wrongdoing involved in the firings, the Bush administration has offered only to allow informal testimony with no transcripts or recordings.
In an attempt to broker a compromise, the Senate committee's top Republican,, asked Leahy on live television if he would be willing to accept the White House's offer and consider subpoenas later as needed.
"One thing we haven't done is asked for a meeting with the president," Specter said to Leahy on CNN.
"Why don't you and (Democratic House committee chair) John Conyers I ask for a meeting with the president? We may be a little tired of dealing with his lawyer."
Leahy responded: "Why don't you and I chat about this tomorrow when we're on the (Senate) floor?"
The charge of "contempt of Congress," is usually levied against an individual for failing to comply with a congressional subpoena to testify or produce document.
Asked if lawmakers would consider such a move against the White House, Conyers: "Well, yes. It means moving forward in the process that would require him to comply with the subpoenas like most other people."
However, Conyers told ABC he hoped negotiations would bear fruit.
"We keep getting stalled. They keep pressing us. We're seeking cooperation. This is not partisan in any way whatsoever," he said.