The United Auto Workers (UAW) union has filed unfair labor practice charges against General Motors and Chrysler-parent Stellantis , saying they have refused to bargain in good faith.

Separately, the UAW said Ford Motor has offered a 9% wage increase through 2027, much less than the 46% wage hike being sought by the UAW.

The current four-year labor agreements covering 146,000 workers at the Detroit Three automakers expire on Sept. 14.

UAW announced its charges on Thursday.