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.

The U.S.’s closest security allies in Asia, along with six Southeast Asian countries, have been given another three weeks to negotiate trade deals — or face higher tariffs.

President Donald Trump on Monday informed Japan and South Korea that 25% tariffs will be imposed starting Aug. 1 on goods sent to the United States.