President Donald Trump has announced new higher tariff rates set to take effect on August 1 for 14 countries, creating even more uncertainty for many who had believed they were making progress on trade talks with the White House.

Trump sent nearly identical notices out to leaders of the 14 nations — primarily spread across Southeast Asia, but also including South Africa, Kazakhstan and Serbia  — on July 7, threatening countries with tariffs rates ranging from 25% for South Korea and Japan, to 36% for Thailand and Cambodia. In each case, the letters concluded that the U.S. must move away from "long-term, very persistent" trade deficits engendered by the countries' tariff and non-tariff trade barriers. 

According to The New York Times, several of the nations targeted for higher rates have been actively engaged in negotiations with the Trump administration for weeks. That included a Thai delegation that had last met with U.S. trade representative Jamieson Greer in late June, and South Korea's newly-elected President Lee Jae Myung, who had sent his top trade negotiator and national security advisor to meet with White House officials just days before Trump sent out the letters outlining the new tariff rates.

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“We are doing our best to bring about a result mutually beneficial to both sides, but we have been unable to establish what each side exactly wanted from the other side," President Lee said on July 3. Shortly after receiving its letter, Thailand's acting Prime Minister Phumtham Wechayachai called the Trump administration's decision "a bit of a contradiction," while South Africa's President Cyril Ramaphosa challenged Trump's claims regarding unfair trade barriers, given that three-quarters of U.S. goods are sold in South Africa with zero tariffs. 

Whether Trump will actually stick to this new timeline remains to be seen, given his penchant for pausing or extending tariff proposals before they're scheduled to take effect. To wit, when asked if the August 1 deadline was firm, he described it as "firm, but not 100% firm." White House Press Secretary Karoline Leavitt indicated that the Trump administration also plans to send out additional tariff letters to at least 12 other countries, but did not specify when that would happen, or which nations would be targeted.