The US president has warned Ottawa and Brussels not to provoke their best friend by retaliating with their own duties

US President Donald Trump has threatened to impose additional tariffs on the European Union and Canada if they collaborate to "do economic harm" to the United States.

Trump's warning comes after the newly-installed Canadian prime minister, Mark Carney, said the old relationship with Washington was "over" and that it was important for Canada to strengthen ties with "reliable partners" in Europe.

"If the European Union works with Canada in order to do economic harm to the USA, large scale Tariffs, far larger than currently planned, will be placed on them both in order to protect the best friend that each of those two countries has ever had!" Trump wrote on his Truth Social platform on Thursday.

On Wednesday, Trump announced plans to impose an additional 25% tariff on hundreds of billions of dollars' worth of imported cars and auto parts beginning next week. The EU's biggest economies and Canada have threatened to retaliate.

In early March, the US imposed a 25% tariff on most Canadian goods, citing a trade imbalance and drug trafficking concerns.

In February, Trump announced plans to introduce a 25% levy on goods imported from the EU, which is set to come into force next week. Both Ottawa and Brussels have responded with their own duties.

The escalating dispute with Canada follows a spate of comments from Trump claiming that the country would be better off as the 51st state of the US. Canada has categorically rejected becoming part of the US.

Washington has long accused the European Union of unfair trade practices, including high tariffs on American goods and restrictive regulatory barriers that disadvantage US companies.

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The Ukraine conflict has also driven a wedge between Brussels and the new administration in Washington. Trump has adopted a more conciliatory approach toward Russia and has initiated peace talks, while the EU has insisted on continuing the supply of lethal aid to Kiev and has considered deploying troops.

(RT.com)