A US federal appeals court on Friday ruled that most tariffs imposed by president Donald Trump under emergency powers were illegal, striking at the heart of his trade policy and setting up a likely battle in the Supreme Court, news agency Reuters reported.Trump has relied heavily on tariffs in his second term, using them as a central tool of US foreign policy to pressure trading partners and push for revised trade agreements. While the duties have helped his administration secure economic concessions, they have also added to uncertainty in financial markets.The ruling by the US court of appeals for the federal circuit in Washington, DC, covered two sets of tariffs – Trump’s “reciprocal” duties imposed in April as part of his trade war and another set announced in February against China, Canada and Mexico. It does not affect other tariffs Trump imposed under separate statutes, including those on steel and aluminum imports.The court observed: “The statute bestows significant authority on the President to undertake a number of actions in response to a declared national emergency, but none of these actions explicitly include the power to impose tariffs, duties, or the like, or the power to tax,” as quoted by the agency.The decision also said Trump had exceeded his authority under the International Emergency Economic Powers Act (IEEPA).Trump had invoked IEEPA, a 1977 law historically used for sanctions and asset freezes, to justify tariffs by declaring a national emergency over persistent US trade deficits and cross-border drug flows. The administration argued that the law’s power to “regulate” imports extended to tariffs.The appeals court rejected that view, saying: “It seems unlikely that Congress intended, in enacting IEEPA, to depart from its past practice and grant the President unlimited authority to impose tariffs. The statute neither mentions tariffs (or any of its synonyms) nor has procedural safeguards that contain clear limits on the President’s power to impose tariffs.”The appeals court put its ruling on hold until October 14, allowing the Trump administration time to seek a reversal from the Supreme Court.Minutes after the ruling, President Donald Trump sharply criticised the judgement, saying if allowed it would be a “ total disaster for the Country”. In a post on his social media platform Truth Social, he attacked the appeals courts as “Highly Partisan’ and asserted that the Supreme Court would rule in his favour.“If these Tariffs ever went away, it would be a total disaster for the Country,” Trump wrote in his post. “If allowed to stand, this Decision would literally destroy the United States of America.”

“The President’s tariffs remain in effect, and we look forward to ultimate victory on this matter,” White House spokesman Kush Desai said in a separate statement, as quoted by CNBC.