U.S. President Donald Trump has begun sending formal tariff notices to foreign leaders, with Japan and South Korea first in line for a 25% tariff on goods imported into the United States starting August 1.

The announcement was made via Trump’s Truth Social account, where he posted the letters addressed to Japanese Prime Minister Shigeru Ishiba and South Korean President Lee Jae-myung. The letters include a warning: any retaliatory tariff measures will result in additional duties from the U.S.

“If for any reason you decide to raise your tariffs, then, whatever the number you choose to raise them by, will be added onto the 25 per cent that we charge,” Trump stated.

He claimed the 25% figure was “far less than what is needed to eliminate the trade deficit” with both countries. Trump encouraged companies from Japan and South Korea to manufacture directly in the U.S. to avoid tariffs and promised fast-track approval processes for projects.

“There will be no tariff if you manufacture products in the U.S. We will fast-track all necessary approvals — professionally and within weeks,” Trump added.

The U.S. President also signaled that more such letters may go out before July 9, the deadline for concluding bilateral trade deals. He emphasized that tariffs could be adjusted based on the strength of each country’s relationship with the U.S.

Meanwhile, Treasury Secretary Scott Bessent said the administration is close to finalizing several trade deals, with a surge of proposals arriving ahead of the deadline. The U.S. has already announced agreements with Vietnam and China, and talks with India remain ongoing, particularly over agriculture and dairy.