Detroit ? Ford Motor Co. workers have overwhelmingly rejected contract changes that would have allowed the automaker to cut labor costs, leaving Ford at a disadvantage to its Detroit rivals as it continues its struggle to return to profitability.

The United Auto Workers union had given local unions until Monday to complete voting. But a person briefed on the voting said Saturday that the contract changes have been rejected by large margins. The person asked not to be named because the UAW hasn’t announced the results yet.