President Donald Trump unveiled the first in a wave of promised letters that threaten to impose higher tariffs rates on key trading partners, including levies of 25% on goods from Japan and South Korea beginning Aug.

Many countries thought they were negotiating in good faith. The White House renewed its “reciprocal” tariff plan anyway, giving countries until Aug. 1 to make offers.

President Donald Trump cranked up the pressure Monday on America’s trading partners, firing off letters to heads of several countries, informing them of their new tariff rate. But at the same time, Trump took some of the edge off by signing an executive action Monday to extend the date for all “reciprocal” tariffs,