WASHINGTON -- U.S. Sen. Arlen Specter today called on President Bush to forge an agreement with Congress on "sharing power" on the Iraq war, just as the Senate prepares to debate resolutions opposing the president's plans to send additional troops.

"It's premature to decide that question. First we've got to see if we can work out with the president an agreement on sharing power. He has shown signs of being willing to do that," said the Pennsylvania Republican, who will join a group of fellow Republican senators in meeting with President Bush later this week.

He spoke after a hearing of the Senate Judiciary Committee, chaired by Sen. Russ Feingold, D-Wis., one of the administration's most ardent critics, who said he plans to introduce a bill that would cut off funding for the war in six months. Several constitutional scholars testified that Congress has considerable power in compelling the president to change course, although a scholar from the University of Virginia, Robert F. Turner, disagreed.

"If Congress doesn't stop this war," Mr. Feingold said, "it's not because it doesn't have the power. It's because it doesn't have the will."

A group called Americans Against Escalation in Iraq today planned to hold a press conference in Philadelphia to put pressure on Mr. Specter.

He hasn't taken a position on any of the Iraq-related bills being considered in Congress, saying that he hopes to avoid a confrontation with the president if an agreement could be reached.

More details in tomorrow's Pittsburgh Post-Gazette.