The Teamsters union and Public Citizen have filed a lawsuit against the Department of Transportation seeking to block the government’s plan to allow Mexican trucks back into the United States, the Wall Street Journal reported.

A federally funded program that retrofitted 76 trucks in Arizona with new $1,600 catalytic converters was terminated after public uproar that some of the money was being spent on Mexican carriers.

U.S. regulators and U.S. truckers who do business in Mexico said they are skeptical that Mexican carriers will participate in the cross-border trucking program in large numbers when the pilot project gets into full swing in the next 60 days.

Top transportation officials of the United States and Mexico last week signed an agreement that will allow Mexican trucks to carry freight beyond border commercial trade zones, which will in turn prompt Mexico to remove $2.4 billion in retaliatory tariffs it imposed on U.S. products.

The United States and Mexico are close to signing a formal cross-border trucking agreement and could do so as early as this month, according to a Mexican government minister, Bloomberg reported.

Cross-border trucking between the United States and Mexico, already beset by political issues and road-safety concerns, faces a serious new problem in the form of a warning from the U.S. State Department.

Public comments on a proposal to allow Mexican longhaul trucks on U.S. highways were largely divided among those who urgently want retaliatory Mexican tariffs ended and those who fear the move would make the nation’s roads less safe and steal jobs from Americans.

If FMCSA can pay for the Mexican trucks to have EOBRs, why not U.S. trucks? Our government is helping out others and yet not putting or keeping the money here in the good old United States of America.

Sen. Mark Pryor (D-Ark.) is the latest member of Congress to send a letter to Transportation Secretary Ray LaHood expressing his strong opposition to a U.S. proposal to buy electronic onboard recorders for Mexican trucks that will travel within the United States.