Japan has raised the issue of auto tariffs with the United States after U.S. President Donald Trump threatened to impose a 25% levy on car imports, a move that would likely deliver a big blow to Japan’s economy.

Tokyo is closely watching any potential impact stemming from higher levies, which the president said might officially be unveiled as soon as April 2. Economists estimate the impact would be substantial given that cars make up the largest component of Japan’s exports, with the U.S. as the No. 1 market.

"We have been raising the issue with the U.S. government, given the importance of Japan’s automobile industry,” Chief Cabinet Secretary Yoshimasa Hayashi said at a news conference on Wednesday. "Japan will first carefully examine the specific details of the measures that will come out and their impact on Japan, and then respond appropriately.”