General Motors Co., fresh off agreeing to a new union contract that is expected to drive up its U.S. labor costs, plans to become the first major auto maker to sell Chinese-made cars in the U.S.

The nation’s No. 1 auto maker by sales early next year plans to start selling the Buick Envision, a midsize sport-utility vehicle made in Shandong province, according to people familiar with the plan. The move would add a third SUV to Buick’s U.S. lineup at a time when such crossovers are among the best selling vehicles in the market.

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