DONALD Trump’s sweeping global tariffs are now at risk after a court has said he doesn’t have the power to impose the levies himself.

A US federal court in New York on Wednesday blocked most of the import taxes from going into effect, ruling that the president had overstepped his authority.

The Court of International Trade ruling is a big setback for Trump, who has sought to reshape global trade and put America first by using its economic heft to cut deals.

Trump has started a global trade war with nearly every country by instituting a minimum 10 per tariff on their exports into the US.

He also slapped a 25 per cent tariff on Mexico and Canada, saying he needed to levies to stop the flow of illegal immigrants and the horror drug Fentanyl.

The court’s order could spell an end to Trump’s international trade war as it bars Trump’s most sweeping tariffs, effectively erasing most of the trade restrictions Trump has announced since taking office.

But Trump is likely to appeal and take the fight all the way to the Supreme Court.

White House spokesman Kush Desai said: “Foreign countries’ nonreciprocal treatment of the Unites States has fueled America’s historic and persistent trade deficits.

“These deficits have created a national emergency that has decimated American communities, left our workers behind, and weakened our defense industrial base – facts that the court did not dispute.

“It is not for unelected judges to decide how to properly address a national emergency. President Trump pledged to put America First, and the Administration is committed to using every lever of executive power to address this crisis and restore American Greatness.”

The ruling does not state that tariffs themselves are illegal, but that the executive branch does not have the authority to impose them without Congress.

The president used a 1977 federal economic emergency law to justify a range of levies.

The three-judge panel wrote in an unsigned opinion: “The question in the two cases before the court is whether the International Emergency Economic Powers Act of 1977 (“IEEPA”) delegates these powers to the president in the form of authority to impose unlimited tariffs on goods from nearly every country in the world.

“The court does not read IEEPA to confer such unbounded authority and sets aside the challenged tariffs imposed thereunder.”

One of Trump’s key aides, Stephen Miller, attacked the ruling in a post on social media saying: “The judicial coup is out of control.”

Trump memorably held up a board showing rates he was about to set individual trading partners in the White House’s Rose Garden when he announced the tariffs as part of a “liberation day”.

China was clobbered with 34 per cent tariffs, Vietnam 46 per cent, Thailand 36 per cent and Cambodia 49 per cent.

Tariffs on China were eventually increased to a whopping 145 per cent as Trump sought to begin negotiations.

The ten per cent on Britain was at the bottom of the sliding scale devised by Trump’s officials.

Markets were thrown into turmoil but calmed after he paused the larger tariffs for 90 days.

He also suspended some of the higher duties pending negotiations with individual countries and blocs.

Britain has signed a new trade deal with Trump following the imposition of the tariffs – how that will be affected is not yet clear.