BRITAIN must “act decisively” to show that it will not be “cowed or bullied” by US tariffs on steel, Labour’s Barry Gardiner said today.

The shadow international trade secretary urged the government to respond “strongly” after US President Donald Trump slapped a 25 per cent levy on imported steel.

Mr Gardiner said: “We believe in a rules-based system, a multilateral system. President Trump doesn’t and we must understand that. He wants to break up that system.

“We have to respond strongly and make it clear that we’re not susceptible to the intimidation and the threats and the bullying.”

Mr Trump originally imposed the tariffs in March, claiming that his country’s reliance on imported metals threatened national security.

The levies have now been extended to the European Union, Canada and Mexico, after they were previously granted exemptions.

According to figures from steel union GMB, the tariffs threaten 34,000 British jobs in the industry.

The region most at risk is Yorkshire and the Humber, where 9,500 jobs could be hit, said GMB. Just behind is Wales with 9,250 jobs at risk.

National secretary Jude Brimble said the government “must act urgently to protect the livelihoods” of the workers.

Fellow steel union Unite condemned the government’s “abject failure” to gain exemptions from US tariffs via the so-called special relationship.

Unite also claimed that the spat showed the need to remain in a customs union with the EU after Brexit.

“The government cannot be a bystander as the threat of a job-destroying trade war increases,” said national officer for steel Tony Brady.