Mexico will allow a union vote at a General Motors plant after a U.S. complaint.

The United States has reached a deal with Mexico to give workers at a General Motors plant in the country the ability to vote on a collective bargaining agreement in “free and democratic conditions.”

It is the first step toward remediation of a complaint the Biden administration filed in May, using a new “rapid response” mechanism in the United States-Mexico-Canada Agreement, which replaced the North American Free Trade Agreement last year. The new agreement included language giving factory workers in the United States, Canada and Mexico the right to form unions and authorized penalties for factories that violated workers’ rights of free association and collective bargaining.

In a statement, Katherine Tai, the United States trade representative, portrayed Thursday’s deal as a win for the Biden administration’s commitment to workers.

“Reaching an agreement with Mexico on a remediation plan shows the U.S.M.C.A.’s potential to protect workers’ rights and the benefits of a worker-centered trade policy,” Ms. Tai said. “Fully implementing and enforcing the U.S.M.C.A. not only helps workers there, it also helps American workers by preventing trade from becoming a race to the bottom.”

The deal comes after the Biden administration asked Mexico in May to review whether labor violations had occurred at the Silao plant, located in the central state of Guanajuato. The administration said it had received information indicating “serious violations” of workers’ rights associated with an April vote on a collective bargaining agreement.

The remediation plan calls for a new vote to be held by Aug. 20, which Mexico’s Labor Ministry will oversee to ensure that the voting area is secure and ballots are safeguarded. If the vote does not occur, the collective bargaining agreement will be terminated, but workers will retain their rights and other unions can negotiate on behalf of workers.

Mexico will send federal inspectors to the plant starting this week and continuing through the vote.