BATH, Maine (AP) The union representing striking workers at Bath Iron Works has requested the assistance of a federal mediator.

More than 4,000 members of Machinists Union Local S6 went on strike Monday after rejecting the company’s final proposal. Both the company and the union said they’re open to resuming negotiations, but that hadn’t happened as of Thursday.

Jay Wadleigh, district business representative for the Machinists, said the request for a federal mediator was made Tuesday, but the company would have to agree to mediation.

There was no immediate comment from the company on Thursday.