DETROIT — Striking General Motors workers will stay on the picket lines for several more days until they vote on a tentative contract agreement with the company.

Factory-level officials from the United Auto Workers union voted to recommend the agreement to members at a daylong meeting in Detroit Thursday. But they also voted not to return to factories unless members approve the deal.

About 49,000 workers have been on strike for more than a month, paralyzing GM's U.S. factories and costing the company an estimated $2 billion.

A tentative, four-year contract with striking General Motors would give workers a mix of pay raises, lump sum payments and an $11,000 signing bonus.

In return, the contract allows GM to proceed with factory closures in Lordstown, Ohio; Warren, Michigan, and near Baltimore.

Details were posted Thursday on the union website as factory level union officials met to decide if they'll approve the deal.

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