Senate Majority Leader Harry Reid says he will try to cut off funding for the Iraq war if President Bush rejects Congress' proposal to set a deadline for ending combat.
The move is likely to intensify the Democrats' rift with the administration, which already contends Democrats are putting troops at risk by setting deadlines.
The House and Senate voted separately in recent weeks to finance the wars in Iraq and Afghanistan but set an end date next year for combat in Iraq.
The House and Senate are working on a final proposal that can be sent to the president by the end of the month.
Bush has said several times he would veto the measure, and Republicans say they'll back him.
Reid says he will join forces with Senator Russ Feingold, one of the Democrats' most liberal members who has long called to end the war by denying funding for it. Reid and others have previously been reluctant to propose cutting funding out of fear it would leave troops in the lurch.
Reid now says he is willing to take the tougher tack considering Bush's refusal to begin pulling out troops.