President Trump on Monday said the U.S will impose 25% tariffs on goods from South Korea and Japan by Aug. 1, while also threatening to hit a dozen other nations with steep import duties by next month.

Trump sent letters to 14 countries threatening them with new tariffs, and the White House said more countries may be included in the coming days.

The letters listed a range of tariffs. Goods entering the U.S. from Japan, South Korea, Malaysia, Kazakhstan, and Tunisia will be subject to a 25 percent levy. There will be a 30 percent levy on South African and Bosnian goods, while imports from Indonesia will be subject to a 32 percent rate.