The union said in a statement it had been negotiating for a collective-bargaining agreement with the steelmaker since June.

Members of the union will cast a deciding vote on the agreement over the next few weeks.

But union negotiations continue with Luxembourg-based ArcelorMittal (ISPA.AS) -- the world's largest steelmaker -- over a new labor contract, after a midnight deadline passed without an agreement.

"We have been exchanging proposals with the company and remain engaged in negotiations," USW president Leo W. Gerard said in a statement.

He added that members of the union will continue to work under the terms set in a 2008 contract while the negotiations are ongoing. The contract, however, has not been formally extended.

The company is restarting blast furnaces idled in the run-up to the contract expiry at midnight on Saturday, Gerard said.

ArcelorMittal operates steel plants in Indiana, Ohio and several other states.

United Steelworkers represents about 850,000 workers in the United States, Canada and the Caribbean.

The deal with U.S. Steel comes a day before the Labor Day holiday on Monday, which honors American workers.

(Reporting by Selam Gebrekidan; editing by Theodore d'Afflisio, Gary Crosse)

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