The U.S. asks Mexico to investigate allegations of labor violations at a G.M. plant.

The Biden administration announced Wednesday that it was asking Mexico to review whether labor violations had occurred at a General Motors plant in the country, a significant step using a new labor enforcement tool in the revised North American trade deal.

The administration is seeking the review under the novel “rapid response” mechanism in the United States-Mexico-Canada Agreement, which replaced the North American Free Trade Agreement and took effect last summer. Under the mechanism, penalties can be brought against a specific factory for violating workers’ rights of free association and collective bargaining.

The administration “received information appearing to indicate serious violations” of workers’ rights at the G.M. facility, in Silao in the central state of Guanajuato, in connection with a recent vote on their collective-bargaining agreement, the Office of the United States Trade Representative said.

The vote was stopped last month amid accusations that the union at the plant had tampered with it, according to news reports. Mexico’s Labor Ministry said on Tuesday that it had found “serious irregularities” in the vote and ordered that it be held again within 30 days.

In a statement, Katherine Tai, the U.S. trade representative, said the announcement on Wednesday “shows the Biden-Harris administration’s serious commitment to workers and a worker-centered trade policy.”

“Using U.S.M.C.A. to help protect freedom of association and collective-bargaining rights in Mexico helps workers both at home and in Mexico, by stopping a race to the bottom,” she said, using the initials for the trade deal. “It also supports Mexico’s efforts to implement its recent labor law reforms.”

In a statement, General Motors said that it believed it had no role in the alleged labor violations and that it had asked a third-party firm to review the matter. The company, which makes Chevrolet Silverado, Chevrolet Cheyenne and GMC Sierra pickup trucks at the Silao plant, said it would cooperate with Mexico’s Labor Ministry and the U.S. government.