Prime Minister Justin Trudeau says there is no justification for the trade war Canada and the U.S. are entangled in.

In a speech aimed at U.S. President Donald Trump, Trudeau did not hold back.

“So today, the U.S. launched a trade war against Canada, their closest partner and ally, their closest friend,” he said.

“At the same time, they’re talking about working positively with Russia, appeasing Putin, a lying, murderous dictator. Make that make sense.”

Overnight, Trump imposed 25 per cent tariffs on virtually all Canadian goods, lobbing a grenade at the Canadian economy and triggering a trade war between the once-close allies.

As the U.S. tariffs came into effect at midnight, so did Canada’s retaliation. The government hit back with an initial $30 billion in tariffs on U.S. goods, with the promise to add another $125 billion more in three weeks’ time.

Canada, said Trudeau, “will not back down from a fight” and will challenge Trump’s moves.

This extraordinary moment in Canadian history comes as the sun sets on Trudeau’s time as prime minister. He has said he will step down after the Liberal Party selects its next leader this Sunday.