Detroit ? The United Auto Workers union reached a tentative four-year contract agreement with Ford Motor Co. on Saturday, avoiding the threat of a strike against the struggling automaker, the union said.

The deal, reached about 2:20 a.m. CDT, must be ratified by the UAW’s approximately 54,000 members covered by the contract at Ford. If approved, it would bring a close to historic negotiations that have yielded agreements designed to return U.S.-based automakers to profitability.