U.S. President Donald Trump announced on July 7 that his administration would impose a 25 percent tariff on imports from South Korea and Japan beginning August 1 as part of a batch of letters going out to foreign countries.

Trump detailed the expected tariff rates in letters to the leaders of Japan and South Korea, also posting them to Truth Social. The president had previously indicated he would send letters to roughly a dozen countries Monday.

“Please understand this 25% number is far less than what is needed to eliminate the Trade Deficit disparity we have with your Country,” Trump wrote to both countries, according to The Hill.

The U.S. president warned that if either nation raised its tariffs in response, the United States would increase its tariffs by the same amount. 

Trump reportedly wrote to South Korea’s president: “As you are aware, there will be no Tariff if Korea, or companies within your Country, decide to build or manufacture product within the United States and, in fact, we will do everything possible to get approvals quickly, professionally, and routinely – in other words, in a matter of weeks.”

Under the “Liberation Day” tariffs announced on April 2, South Korea was hit with a 25-percent tariff and Japan hit with a 24-percent tariff, so Monday’s announcement amounts to an extension of the negotiation deadline, which was initially set for Wednesday.

The New York Post reports that also getting letters Monday were Bangladesh (facing a 35% rate), Bosnia and Herzegovina (30%), Cambodia (36%), Indonesia (32%), Kazakhstan (25%), Laos (40%), Malaysia (25%), Myanmar (40%),  Serbia (35%), South Africa (30%), Thailand (36%) and Tunisia (25%).