The move sets up a showdown with Democratic leaders, who insist that the course in Iraq must be changed. Employing often-heated rhetoric, each side has accused the other of denying needed funds to troops.

At the congressional signing ceremony that preceded the veto, Senate Majority Leader Harry Reid (D-Nev.) hailed the bill, saying it “helps us more effectively fight terrorism and strengthens United States security. It redeploys our troops out of an intractable civil war. It ensures our troops are combat-ready before being deployed in Iraq. It provides them with all the resources needed on the battlefield and when they return.”

Despite the apparent stalemate on the issue, Senate Minority Leader Mitch McConnell (R-Ky.) voiced hope that a compromise could be reached.

“It is my sense that on the Democratic side here in the Senate there is interest in moving forward, getting a bill that the president can sign at the earliest possible time,” McConnell told reporters.

He added that there are “some kinds of benchmarks that might well achieve bipartisan support and might actually even conceivably be helpful to the effort in Iraq.”