WASHINGTON, D.C. — The U.S. Senate has thumbed its nose at George Bush and his threat of a presidential veto and voted to back tougher safety standards for Mexican trucks entering the U.S.

A bipartisan vote of 70-30, the Senate brought a halt to a Republican filibuster that was aimed at forcing a watering-down of the regulations.

Thursday’s vote sent a clear message that it is only a matter of time before the Senate approves the proposed requirements, which include inspections of Mexican trucks and drivers, audits of Mexican trucking companies, and more inspectors and scales at the 27 U.S. border stations.

Last month, the House approved an even more restrictive plan to completely block Mexican trucks from being able to drive throughout the U.S. and beyond the approximately 20-mile wide commercial zone north of the Mexico-U.S. border.

Bush has threatened to veto that version as well. Republicans say the standards would be a direct violation of the 8-year-old NAFTA, because they imposed tougher requirements on Mexico than exist for Canadian trucks.

“It is wrong for the Congress to discriminate against Mexican trucks,” Bush said at the White House shortly before the vote. “And I urge the Senate to reject an amendment to the transportation bill that would clearly discriminate against Mexican truckers.”