President Donald Trump on Monday set a 25% tax on goods imported from Japan and South Korea, as well as new tariff rates on a dozen other countries.

The country’s new president, in office for a little over a month, had just dispatched his senior deputies to Washington to try to work out a trade deal.

While South Korean imports to the U.S. face 25% tariffs, the same as Trump promised in April, the rate on Japan has been raised by 1 percentage point to 25%.

In letters so far to 14 countries, including smaller exporters to the United States such as Serbia, Thailand and Tunisia, Trump hinted at opportunities for additional negotiations, even while warning that reprisals would draw a like-for-like response.

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

Secretary of State Marco Rubio met counterparts in Southeast Asia during his first visit to the region since taking office.

Trump imposes tariffs up to 40% on 14 countries, pressuring allies to shift production to the US and avoid ties with BRICS. Tensions mount globally.