WASHINGTON (AP) — Pepco and its union say they have reached a tentative contract agreement that will likely avert a strike.

Pepco says the preliminary agreement is subject to a vote by the International Brotherhood of Electrical Workers Local 1900.

The union posted a message on its website Sunday saying they had reached an agreement on a four-year contract after daylong negotiations.

Both sides have declined to provide specific details on the agreement.

Union President James A. Griffin says the union leadership is recommending that members vote to approve the contract. Previously he said his biggest concern was a proposed change to the workers’ health and welfare plans.

The company and union were at an impasse for months. The company’s previous offer was rejected 5 to 1 in a vote last month.

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