Latest tariffs imposed as markets reel from a dizzying series of back-and-forth announcements on trade.

United States President Donald Trump’s sweeping tariffs on steel and aluminium imports have taken effect and are set to escalate tensions with US trading partners.

The 25 percent tariffs on all imports of the metals into the US came into effect on Wednesday as governments and markets around the world reeled from a dizzying series of back-and-forth announcements on trade made by Trump in recent days.

The move drew swift retaliation from Canada and the European Union.

Canada, the biggest foreign supplier of steel and aluminium to the US, announced 25 percent retaliatory tariffs on goods including steel, aluminium, computers, sports equipment and other products worth 29.8 billion Canadian dollars (US$20.7bn) in total.

The European Commission, the executive arm of the EU charged with coordinating trade matters, said it would impose counter tariffs on up to 26 billion euros (US$28bn) of US goods – often with more symbolic than economic impact – from next month.

Nevertheless, commission President Ursula von der Leyen told reporters she had tasked Trade Commissioner Maros Sefcovic to resume talks with US officials on the matter.

China’s Ministry of Foreign Affairs said Beijing would take all necessary measures to safeguard its rights and interests while Japanese Chief Cabinet Secretary Yoshimasa Hayashi said the move could have a major impact on US-Japan economic ties.

Close US allies Britain and Australia criticised the blanket tariffs with Australian Prime Minister Anthony Albanese saying the move was “against the spirit of our two nations’ enduring friendship”. However, both countries ruled out immediate tit-for-tat duties.

‘America first’

On Tuesday, Trump threatened to impose 50 percent tariffs on Canadian aluminium and steel before reversing course just hours later.

Trump’s senior economic adviser, Peter Navarro, confirmed in an interview with the US business news channel CNBC later on Tuesday that the tariffs would not be imposed after the Canadian province of Ontario agreed to temporarily suspend a surcharge on electricity exports to three US states.

Trump had cited Ontario Premier Doug Ford’s decision to impose the surcharge on electricity exports to Minnesota, Michigan and New York in his Truth Social post announcing the tariffs hike.

“Just tamp it down, please, over there,” Navarro said in his CNBC interview, addressing Canada.

Trump last week imposed tariffs on Canada, Mexico and China before announcing he would delay some of the duties until April 2.

The US president has also flagged plans for “reciprocal” tariffs on the European Union, Brazil and South Korea from early next month.

The uncertainty surrounding Trump’s “America first” agenda has roiled stock markets as investors struggle to gauge whether his tariffs are here to stay or a bargaining tactic.

The US benchmark S&P 500 fell 0.8 percent on Tuesday, after tumbling 2.7 percent on Monday.

The tech-heavy Nasdaq Composite dipped 0.2 percent, following a 4 percent slump the previous day.

Although they apply to all countries, the latest tariffs will have a significant impact on Canada because the country supplies about 50 percent of US aluminium imports and 20 percent of its steel imports.

Other major steel suppliers to the US include Brazil and Mexico while the United Arab Emirates and South Korea are among the top suppliers of aluminium.

US-Canada relations have been especially strained under Trump, who has repeatedly threatened to annex the country in addition to launching successive trade salvoes.