WASHINGTON -- Thirty-one House members filed suit against President Bush Tuesday in an effort to block the president from withdrawing from the 1972 Anti-Ballistic Missile Treaty.

The United States officially leaves the treaty on Thursday, six months after Bush announced his intentions to do so. The Pentagon plans an earth-breaking ceremony on Saturday at Fort Greely, Alaska, to begin construction on the first portion of a new missile interceptor system.

Rep. Dennis Kucinich, D-Ohio, the lead plaintiff, said the president does not have the authority to unilaterally withdraw from a treaty and should first seek the consent of Congress. "The Constitution of the United States is being demolished, and we need to challenge that in court," he said.

The lawsuit, filed in U.S. District Court for the District of Columbia, also names Defense Secretary Donald H. Rumsfeld and Secretary of State Colin Powell as defendants. The plaintiffs are all Democrats, except for one independent who usually votes with Democrats.

It states that while the Constitution is silent on the role of Congress in treaty terminations, treaties have the status of "supreme law of the land" equivalent to federal laws and that laws can be repealed only by an act of Congress.

"I am troubled that many in Congress appear willing to cede our constitutional responsibility on this matter to the executive branch," said Sen. Russ Feingold, D-Wis. He tried unsuccessfully Monday to bring a resolution to the Senate floor stating that the president cannot withdraw from the treaty without Senate approval.

Kucinich last week tried to get the House to vote on a similar resolution, but House Republicans unanimously rejected a motion to bring the issue to a vote.