The Biden administration is invoking provisions in a new trade agreement to ask Mexico to look into accusations of labor violations at an auto-parts plant near the U.S. border.The action, announced Wednesday by the Labor Department and the Office of the United States Trade Representative, follows a complaint by groups including the A.F.L.-C.I.O., the nation’s largest federation of unions, that workers were being denied the rights of free association and collective bargaining.The A.F.L.-C.I.O. said workers at the Tridonex plant in Matamoros, across the border from Brownsville, Texas, had been harassed and fired over their efforts to organize with an independent union in place of one controlled by the company. Tridonex is owned by Cardone Industries, an aftermarket auto-parts manufacturer based in Philadelphia.It is the second time that the United States has sought Mexican review of a labor rights matter under the United States-Mexico-Canada Agreement, which took effect last summer. The accord has a “rapid response” mechanism that provides for complaints to be brought against and for penalties to be applied to an individual factory.“This announcement demonstrates our commitment to using the tools in the agreement to stand up for workers at home and abroad,” Katherine Tai, the U.S. trade representative, said in a statement, noting that Mexico has 10 days to agree to conduct a review and, if it agrees, 45 days to remedy the situation.Last month the United States asked Mexico to review whether labor violations had occurred at a General Motors plant in the central state of Guanajuato in connection with a recent vote on a collective bargaining agreement. Mexico agreed to the request the same day.