The European Union rushed to appeal for trade stability in the wake of the ruling, calling for “predictability in the trading relationship.” 

Brussels said it was in touch with the Trump administration as it seeks “clarity on the steps they intend to take in response to this ruling,” European Commission deputy chief spokesperson Olof Gill said in a statement.

The U.K. — which, together with Australia, was hit by the lowest reciprocal tariff rate — downplayed the impact, saying it expected its “privileged trading position with the U.S. to continue,” despite the ruling. 

“This is a matter for the U.S. to determine but we will continue to support U.K. businesses as further details are announced,” a U.K. government spokesperson said, adding that it was working with the Trump administration to “understand how the ruling will affect tariffs for the U.K. and the rest of the world.”

Initial reactions from other capitals reflected a common desire to avoid any fresh escalation after Trump’s first-year tariff offensive upended the postwar trade order and shook the trust of America’s closest allies. There was also concern that the Supreme Court ruling did not provide much clarity on whether, and how, the billions in tariffs paid might be refunded.

The decision was “a positive sign that checks and balances still work in the U.S. However, it is unlikely to lead to less erratic and more rational cooperation,” Roland Theis, a senior lawmaker from German Chancellor Friedrich Merz’s center-right party, told POLITICO.