US President Donald Trump’s decision to reimpose tariffs on steel and aluminum imports took effect on Wednesday, triggering swift retaliation from key trading partners, including the European Union, China, and Canada.

The new measures restore a 25% tariff on all imported steel and aluminum, extending duties to hundreds of downstream products such as nuts, bolts, and soda cans. The move aims to protect American metal producers but has raised concerns over potential economic fallout.

The European Commission quickly responded, announcing plans to impose counter-tariffs worth €26 billion ($28 billion) on US goods starting next month. Commission President Ursula von der Leyen called for dialogue and warned that escalating trade tensions could harm global economies.

China and Japan also voiced concerns, with Beijing vowing to take “necessary measures” to protect its interests and Tokyo warning of possible economic repercussions. Close US allies, including Canada, Britain, and Australia, criticized the move. Canada is considering reciprocal actions, while Britain’s trade minister, Jonathan Reynolds, said “all options” were under review.

The tariffs hit Canada hardest, as it is the top foreign supplier of steel and aluminum to the US. Prime Minister Justin Trudeau’s incoming successor, Mark Carney, has yet to engage directly with Trump on the issue. Canadian officials have floated possible non-tariff responses, such as restricting oil exports.

US steelmakers welcomed the decision, arguing it would protect domestic jobs and industry. However, economists warn the move could slow growth and contribute to inflation amid ongoing global trade uncertainties.