Trump’s sudden decision to hike his new tariff rate to 15% is ‘something of an eff you’ to the U.K., which thought it had a better deal for 10%

Less than 24 hours after President Donald Trump signed an order establishing a new 10% global tariff, he announced an increase to 15%, upending one of his signature trade deals in the process.

The abrupt change followed the Supreme Court’s ruling Friday that struck down his tariffs under the International Emergency Economic Powers Act. Hours after the decision, he imposed a 10% rate under Section 122 of the 1974 Trade Act, then hiked the new duty on Saturday morning.

While experts have pointed out the Section 122 tariffs are also legally dubious, it could take months to sort through any court challenge. And the new rate can only be in effect for up to five months.

But unlike Trump’s attempt to invoke the IEEPA levies, the new ones must be applied uniformly across all trading partners, meaning everyone must face a 15% rate.

That conflicts with the Trump administration’s trade deal reached last year that set a 10% rate on imports from the U.K.

British Prime Minister Keir Starmer notably took a more conciliatory approach to Trump’s stunning “Liberation Day” tariffs last year, and Trump administration officials held up the U.K. trade deal a...