WASHINGTON (CNN) -- Democratic Congressional leaders officially sent the Iraq spending measure to the White House Tuesday, defying President Bush's repeated pledge to veto the legislation.

Senate Majority Leader Harry Reid, D-Nevada, and House Speaker Nancy Pelosi, D-California, held a brief ceremony on Capitol Hill to officially enroll the measure -- a necessary step before any legislation is sent to the White House, but one that is rarely done in public.

"We, as an equal branch of government with that of the executive, are sending the president a piece of legislation that is extremely, extremely important," Reid said during the signing ceremony. "As we know, the president has put our troops in the middle of a civil war. Reality on the ground proves what we all know: A change of course is needed."

President Bush will make a statement Tuesday at 6:10 p.m., about two hours after he receives the $124 billion war-spending bill that calls for the withdrawal of American combat troops from Iraq, the White House said.