President Donald Trump has ordered an investigation to determine whether to impose new tariffs on imported light-duty vehicles and parts following a tweet promising "big news" for the auto industry.

The order came after a meeting between Trump and Secretary of Commerce Wilbur Ross on May 23 in which the two discussed "the current state of our automobile industry," according to a White House statement. Ross initiated the investigation under Section 232 of the Trade Expansion Act of 1962 into imports of vehicles, including light trucks, SUVs, vans, and automotive parts to determine their impact on national security.

"Core industries such as automobiles and automotive parts are critical to our strength as a nation," according to the statement.

The move would likely impact non-Detroit automakers who don't operate a U.S. assembly plant.

"There is evidence suggesting that, for decades, imports from abroad have eroded our domestic auto industry," Ross said in a statement. "The Department of Commerce will conduct a thorough, fair, and transparent investigation into whether such imports are weakening our internal economy and may impair the national security."

In the past 20 years, imports of passenger vehilces have grown to 48% from 32% of the cars sold in the U.S.

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