President Bush said Monday he will send the pending Colombia free-trade agreement to Congress, setting up a showdown with Democrats who strongly oppose the pact.

“The need for this agreement is too urgent, the stakes for our national security too high to allow this year to end without a vote” on the agreement, Bush said. “The administration is eager to work with members from both parties to ensure this vote is a positive one.”

Bush signed the transmittal document Monday, but the House will not receive it until members reconvene Tuesday. By sending the implementing legislation to Capitol Hill, the administration will force an up-or-down vote on the measure within 90 legislative days under fast-track rules which expired June 30. The Colombia deal was negotiated under the old law.

Under the Constitution, the House must act first because the measure would affect revenue. A final Senate vote would occur in September if both chambers make use of the maximum 90 days.

Last week, House Speaker Nancy Pelosi , D-Calif., advised the White House not to send the legislation to Congress now. But House GOP members put pressure on Democrats to vote on the pact as soon as possible.

“It’s my hope the majority leadership will bring this agreement to the floor without further delay, and it’s my expectation the Colombian pact will be passed if members are given a chance to fully examine all the facts,” said House Minority Whip Roy Blunt , R-Mo.

House Minority Leader John A. Boehner , R-Ohio, said the trade deal would help U.S. farmers and businesses.

Democrats oppose the trade agreement, saying the Colombian government has not taken sufficient steps to reduce violence against union members. Republicans counter that Colombia has worked hard to crack down on right-wing paramilitary groups blamed for much of the violence against labor activists.

Democrats sharply criticized Bush’s decision to submit the implementing legislation to Congress before securing support from the party’s leadership.

“The president is making a big mistake,” said Finance Committee Chairman Max Baucus of Montana.

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