Washington, March 5 : US President Donald Trump has warned Canada that he will escalate his trade war after Prime Minister Justin Trudeau announced retaliatory tariffs on US goods.

Trump's remark came after Trudeau said on Tuesday that Canada will be implementing 25 per cent tariffs against $155 billion worth of American products.

On Tuesday itself, US President Trump posted on his social media platform Truth Social, "Please explain to Governor Trudeau, of Canada, that when he puts on a Retaliatory Tariff on the US, our Reciprocal Tariff will immediately increase by a like amount!"

Trump's 25-per cent tariffs on imports from Mexico and Canada took effect on Tuesday, prompting Trudeau to announce retaliatory tariffs on more than $100 billion of American goods that will take effect over 21 days.

Trump has repeatedly referred to the Canadian Prime Minister as the "Governor" of Canada in recent weeks as he called for the country to become the US's 51st state.

Trudeau told reporters in Ottawa on Tuesday that Trump's "dumb" trade war was motivated by a desire "to see a total collapse of the Canadian economy because that'll make it easier to annex us".

"Now, first of all, that's never going to happen," said the Canadian leader.

"But yeah, he can do damage to the Canadian economy ' but he is rapidly going to find out, as American families are going to find out, that that's going to hurt people on both sides of the border."

Canada said it will challenge the US measures at the World Trade Organisation and through the US-Mexico-Canada trade agreement.

"Canadians are reasonable and we are polite, but we will not back down from a fight," said Trudeau, who will step down as Prime Minister after the governing Liberal Party chooses a new leader on Sunday.

Ontario premier Doug Ford said he would issue a 25-per cent export tax on electricity sold to the US and may later cut it off completely if the US tariffs persist. In 2023, Ontario powered 1.5 million homes in Michigan, New York and Minnesota.

Meanwhile, Mexican President Claudia Sheinbaum joined Canada and China ' which was also hit Tuesday with a doubling of duties on goods to 20-percent ' in promising to respond to the tariff hikes imposed by the Trump administration.

"There is no motive or reason, nor justification that supports this decision that will affect our people and our nations," she said during a daily news conference in Mexico City, signalling that she would announce US products to be targeted by Mexico on Sunday.

Sheinbaum took issue with a White House "fact sheet" published on Monday, which repeated the claim that Mexican drug trafficking continues because of "an intolerable relationship" with the government, slamming the allegations as "offensive, defamatory and without support".

Recently Mexico's government seized more than a tonne of the opioid fentanyl, dismantling 329 methamphetamine labs, and extraditing 29 drug cartel figures to the US last week.

Trump has also said he was taking action to combat fentanyl trafficking via the US's northern border, accusing Ottawa of failing to do enough to stem the flow of the drug and its precursor chemicals into the US. Trudeau said the claim was "completely bogus, completely unjustified, completely false".

Meanwhile Beijing announced it would respond with tariffs of up to 15 per cent on a range of US farm exports and expanded the number of US companies subject to export controls and other restrictions.

/IANS