Global tariffs introduced by US president Donald Trump have been ruled unlawful and have been blocked by a US federal court.

The Court of International Trade found that Trump lacked the authority to impose tariffs on nearly every country last month.

Trump had previously said the tariffs were necessary due to a national emergency, but the court ruled in favour of five small businesses who brought the lawsuit forward.

These businesses import goods from countries affected by the high tariffs and marks the first major legal challenge to the new tariffs.

A three-judge panel said the International Emergency Economic Powers Act (IEEPA), which Trump used to justify rising tariffs, is not a valid reason for him to impose such tariffs.

They wrote: “The Worldwide and Retaliatory Tariff Orders exceed any authority granted to the President by IEEPA to regulate importation by means of tariffs.”

The Trump administration put in for an appeal minutes after the ruling. The ruling allows the US government 10 days to complete the process of stopping the tariffs—but most are already suspended.

Following “liberation day” in April, many countries faced a huge hike in tariffs. 

Trump has since lowered tariffs on Chinese imports from 145% to 30%, with the US and UK agreeing on a new deal which sees a 10% duty on most goods from the UK.

He did, however, threaten the EU with tariffs of 50%, but delayed these duties on European goods until July 9.