U.S. President Donald Trump on Tuesday said he would impose a 50% tariff on imported copper and soon introduce long-threatened levies on semiconductors and pharmaceuticals, broadening his trade war that has rattled markets worldwide.

President Trump said Japan and South Korea would face tariffs of 25 percent unless they reached an agreement with the United States. Other countries received notice of higher levies.

President Donald Trump has threatened steep tariffs on America’s trading partners, sending letters to more than a dozen world leaders, warning they have less than a month to strike a deal.