President Donald Trump is scheduled to sign an executive order easing the impact of his auto tariffs, preventing duties on foreign-made vehicles from stacking on top of other levies and lessening charges on parts from overseas used to make vehicles in the US.

WASHINGTON—President Trump is expected to soften the impact of his automotive tariffs, preventing duties on foreign-made cars from stacking on top of other tariffs he has imposed and easing some levies on foreign parts used to manufacture cars in the U.

U.S. automakers are set to get a break on some of the sweeping tariffs President Donald Trump is imposing. Yet even with the new waivers, the outlook for America's longest-lived carmakers remains cloudy, with General Motors saying Tuesday it was "reassessing" its earnings guidance in light of the uncertainty over the tariffs impact.