In September, Mexico and the United States said they had resolved an earlier complaint under USMCA, saying workers at auto-parts plant VU Manufacturing in northern Mexico were able to elect the union of their choice.

"Despite this facility taking positive actions in 2022, some of the failures we identified previously appear to be recurring," said U.S. Trade Representative Katherine Tai on Monday.

Michigan-based VU Manufacturing, who produces interior car parts including arm rests and door upholstery, did not immediately reply to a request for comment.

(Reporting by David Shepardson)