President Bush gave the go-ahead yesterday for Mexican trucks to travel U.S. roads beyond commercial border zones, where they have been restricted while inspection sites and new regulations were put in place.

"The president was pleased to take this action today. He has made very clear we feel we have an important obligation to our neighbors to the south to live up to our international obligation, and also have an important obligation to ensure American roads are safe. And his action today takes both of those into account," White House spokeswoman Claire Buchan said.

The decision comes nearly a year after Bush said he wanted to allow Mexican trucks on U.S. roads, in compliance with the North American Free Trade Agreement.

The trucks and buses won't be on U.S. highways until the Department of Transportation reviews carriers' applications. The department then must grant qualifying carriers provisional operating authority, the DOT said in a statement.

Dave Longo, a Transportation Department spokesman, said the first Mexican trucks could be on U.S. roads "within a month or so."

"President Bush has made good on his commitment to open the border to international trucking and cross-border regular route bus service. This will help increase trade between our countries," Transportation Secretary Norman Y. Mineta said in a statement.

Bush's decision also comes just after a visit by Secretary of State Colin J. Powell with Mexico President Vicente Fox in Mexico, where immigration and other binational issues were discussed.

Bush's action yesterday modifies a 1982 moratorium that banned Mexican trucks from the United States.

In response, Mineta ordered the Transportation Department's Federal Motor Carrier Safety Administration to act on 130 applications received from Mexican-based carriers and bus companies that want to move cargo across the U.S.-Mexican border or provide regular service between Mexico and the United States.

"Mexican carriers and drivers must meet the same standards as U.S. operators," Mineta said.

Last year, an estimated 63,000 Mexican trucks crossed the U.S.-Mexican border, making 4.3 million crossings, officials said.

Mexican trucks were to have full access to U.S. roads beginning in 2000 under NAFTA, signed by the United States, Mexico and Canada in 1993.

But Congress delayed their entry twice amid concerns about safety and pressure from labor groups. An arbitration panel ruled in 2000 that the United States was violating NAFTA by refusing to comply, but it also allowed the United States to impose safety measures.

Bush pledged to comply with NAFTA and Congress agreed after much debate. But Congress also required that more inspectors be hired and full inspection sites be built at ports. It also required Mexico to limit truckers' driving hours and create a commercial driver's license database.

Carriers will be required to have alcohol and drug testing in place to pass the safety check.

The Transportation Department's inspector general also had to certify that safety measures were in place and Mineta had signed off on the assessment.

"This objective has been met by having in place a sufficient number of inspectors, adequate facilities and space for inspections, measures to ensure that licenses are valid and that motor carrier firms pass safety and compliance reviews," said Kenneth Mead, DOT inspector general.