SHANGHAI—China will reduce its import tariff on autos from 25% to 15% starting July 1 in a concession to U.S. trade complaints, but the move is likely to pay the biggest benefits to German auto makers and Chinese consumers.

Import tariffs on auto parts will also be cut, falling to 6% from between 8% and 25%, the Customs Tariff Commission of the State Council, China’s cabinet, said Tuesday. China’s Ministry of Finance called the action an “important measure in further opening up” the Chinese economy.

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