The U.S. Senate voted Tuesday to block a one-year experiment allowing Mexican trucks to transport cargo past a commercial zone along the border, the Associated Press reports. The Senate's 75-23 vote will block funding next fiscal year for the Department of Transportation's administration of the pilot program, setting up a potential veto showdown with President Bush. The action came one day after a truck full of mining explosives crashed in Mexico's northern state of Coahuila, killing 34 and injuring 150. Opponents of opening the border, including the Teamsters, said Mexican trucks are unsafe and the U.S. government's ability to regulate them unreliable. A government audit last week said seven states, including New Mexico, were unprepared, AP reports. John Hill, head of the Federal Motor Carrier Safety Administration, said the vote was in favor “protectionism.”