The United Auto Workers union asked the workers at Stellantis to authorize a strike, accusing the French-Italian car maker of breaking its contract promises, UAW President Shawn Fain said in a letter to the union’s U.S. chapters on Friday.

“We unanimously recommend to the membership that every UAW worker at Stellantis prepare for a fight, and we all get ready to vote YES to authorize a strike at Stellantis,” Fain wrote in the letter that the UAW shared in a post on Facebook.

The union’s grievances center around Stellantis’ product and investment commitments made during contract negotiations last autumn.

“We reviewed the serious violations of our contract and patterns of illegal behavior by Stellantis. The evidence is clear that CEO Carlos Tavares is steering Stellantis on a crash course that will cause our members tremendous harm,” the letter on Friday added.

Stellantis reiterated that it has honored its commitments with the UAW under an agreement reached in 2023.