A US federal court has ruled that President Donald Trump exceeded his authority by imposing sweeping global tariffs, declaring them unconstitutional. The Court of International Trade found that the 1977 International Emergency Economic Powers Act (IEEPA) does not grant the president unilateral power to regulate trade through tariffs—a power the Constitution reserves for Congress.

The ruling came in response to a lawsuit filed by the Liberty Justice Center on behalf of small businesses affected by the tariffs. The court noted that the administration’s justification did not meet the legal threshold of an “unusual and extraordinary threat”, according to BBC.

The White House promptly filed an appeal, arguing that the tariffs were necessary for national economic security and aligned with the president's "America First" strategy. The case is one of several judicial challenges to Trump's trade policies, which have triggered instability in global markets since April.