Canada will be implementing 25% tariffs against 155 billion Canadian dollars worth of American goods, Canadian Prime Minister Justin Trudeau said in a press conference Tuesday.

Speaking from Ottawa, Trudeau said there was “absolutely no justification or need whatsoever” for the tariffs imposed by the US on Canada, which went into effect today.

“The United States launched a trade war against Canada, its closest partner and ally, their closest friend. At the same time they’re talking about working positively with Russia, appeasing Vladimir Putin: a lying, murderous dictator. Make that make sense,” the prime minister said.

The prime minister explained that 30 billion Canadian dollars worth of US goods would see tariffs immediately, while the remaining 125 billion Canadian dollars worth of goods would see tariffs in 21 days.

Canadians are reasonable, and we are polite. But we will not back down from a fight. Not when our country — and the wellbeing of everyone in it — is at stake,” he said.

Trudeau added that Canada will file claims at the World Trade Organization, but in the meantime, “our tariffs will remain in place until the US tariffs are withdrawn and not a moment sooner.”

The prime minister also again hit back against US assertions about Canada being unwilling to help in the fight against illegal fentanyl.

He said the legal pretext Trump presented for the justification of the tariffs —“that Canada is apparently unwilling to help in the fight against illegal fentanyl” — is “totally false.”

“Our border is already safe and secure far less than 1% of fentanyl flows and less than 1% of illegal crossings into the United States comes from Canada,” he said.

Correction: An earlier version of this post misstated the currency of the goods that will see the tariffs. It is Canadian dollars.