WASHINGTON – A new Mexican cross-border truck pilot program with the U.S. could be up and running in four to six months, U.S. trade officials say.

According to the Wall Street Journal., U.S. Trade Representative Ron Kirk told attendees of an annual NAFTA meeting that negotiations with the Mexicans about the launch of the program will begin next week.

The U.S. could therefore open its border to select Mexican carriers before the summer, Kirk added.

Last week, the Obama administration unveiled a "concept document" for allowing once again for Mexican trucks to cross the border beyond the 20-mile commercial restriction zone.

The announcement comes two years after a Democratic Congress cancelled a similar demonstration program by the Bush administration.

The optimism follows last week’s release of a "concept plan" by Transportation Secretary Ray LaHood for reopening the U.S.-Mexico border to long-distance trucking.

In the meantime, Mexican economic minister Bruno Ferrari said the country will stop rotating the list of tariffs on U.S. goods but a general list will remain in place until a full agreement is reached on the truck program.