U.S. automakers worry that President Donald Trump's agreement to tariff Japanese vehicles at 15% would put them at a competitive disadvantage, saying they will face steeper import taxes on steel, aluminum and parts than their competitors.

The preliminary agreement suggests there is a path forward to lowering the auto duties on other major trading partners, as well.

Shares of General Motors , Ford Motor , and Jeep-maker Stellantis , some of the biggest automakers in the U.S., rallied on Wednesday after news of a trade deal that will reduce tariffs on imported Japanese cars,