President Donald Trump on Saturday signed an order to impose stiff tariffs on imports from Mexico, Canada and China — fulfilling one of his post-campaign commitments to voters that threatened to spark higher inflation and disrupt businesses across North America as the countries vowed harsh measures in response.

Mexico's president immediately ordered retaliatory tariffs and Canada's prime minister said it was “prepared” to quickly respond. Trump’s order includes a mechanism to escalate the rates if the countries retaliate against the U.S.

The decision throws the global economy and Trump's own political mandate to combat inflation into possible turmoil, though the Republican president posted on social media that it was necessary “to protect Americans.”

The tariffs risk an economic standoff with America's two largest trading partners in Mexico and Canada, upending a decades-old trade relationship with the possibility of harsh reprisals by those two nations. The tariffs also if sustained could cause inflation to significantly worsen, possibly eroding voters' trust that Trump could as promised lower the prices of groceries, gasoline, housing, autos and other goods.

Trump declared an economic emergency in order to place duties of 10% on all imports from China and 25% on imports from Mexico and Canada. But energy imported from Canada, including oil, natural gas and electricity, would be taxed at a 10% rate.

The tariffs would go into effect on Tuesday, setting a showdown in North America that could potentially sabotage economic growth. A new analysis by the Budget Lab at Yale laid out the possible damage to the U.S. economy, saying the average U.S. household would lose the equivalent of $1,170 in income from the taxes. Economic growth would slow and inflation would worsen — and the situation could be worse if Canada, Mexico and China retaliate.

Responding on X, Mexican President Claudia Sheinbaum said she had instructed her economy secretary to implement a response that includes retaliatory tariffs and other measures in defense of Mexico’s interests.

"We categorically reject the White House’s slander that the Mexican government has alliances with criminal organizations, as well as any intention of meddling in our territory,” Sheinbaum wrote.

“If the United States government and its agencies wanted to address the serious fentanyl consumption in their country, they could fight the sale of drugs on the streets of their major cities, which they don’t do and the laundering of money that this illegal activity generates that has done so much harm to its population.”

Canadian Prime Minister Justin Trudeau on Saturday said that Canada is ready to address the tariffs the U.S. government announced. On a message on his X account, he was to talk to Sheinbaum about the U.S. administration decision, and later he will speak to Canadians.

“We did not want this, but Canada is prepared,” he said.

Trump says tariffs on Canada and Mexico coming Saturday

Meanwhile, the Premier of Canadian province of British Columbia, David Eby, called on residents to stop buying liquor from U.S. “red” states and remove American alcohol brands from government store shelves as a response to the tariffs.

In a televised message, Eby deemed the Trump’s administration decision as “a declaration of economic war against a trusted ally and friend” and that he will stand up for his citizens and all Canadians in general.

“Effective today, I have directed B.C. liquor sales to immediately stop buying American liquor from red states,” he said. “Liquor store employees will be removing the most popular of these brands from government store shelves.”

A senior U.S. administration official, insisting on anonymity to brief reporters, said the lower rate on energy reflected a desire to minimize any disruptive increases on the price of gasoline or utilities. That's a sign White House officials understand the gamble they're taking on inflation. Price spikes under former President Joe Biden led to voter frustration that helped to return Trump to the White House last year.

The order signed by Trump contained no mechanism for granting exceptions, the official said, a possible blow to homebuilders who rely on Canadian lumber as well as farmers, automakers and other industries.

The Trump administration put the tariffs in place to force the three countries to stop the spread and manufacturing of fentanyl, in addition to pressuring Canada and Mexico to limit any illegal immigration into the United States.

The official did not provide specific benchmarks that could be met to lift the new tariffs, saying only that the best measure would be fewer Americans dying from fentanyl addiction.

The order would also allow for tariffs on Canadian imports of less than $800. Imports below that sum are currently able to cross into the United States without customs and duties.

Trump tells Davos leaders to invest in US to avoid tariffs

“It doesn’t make much economic sense,’’ said William Reinsch, senior adviser at the Center for Strategic and International Studies and a former U.S. trade official. “Historically, most of our tariffs on raw materials have been low because we want to get cheaper materials so our manufacturers will be competitive ... Now, what’s he talking about? He’s talking about tariffs on raw materials. I don’t get the economics of it.’’

The Republican president is making a major political bet that his actions will not significantly worsen inflation, cause financial aftershocks that could destabilize the worldwide economy or provoke a voter backlash. AP VoteCast, an extensive survey of the electorate in last year's election, found that the U.S. was split on support for tariffs.

With the tariffs, Trump is honoring promises that are at the core of his economic and national security philosophy. But the announcement showed his seriousness around the issue as some Trump allies had played down the threat of higher import taxes as mere negotiating tactics.

The president is preparing more import taxes in a sign that tariffs will be an ongoing part of his second term. On Friday, he mentioned imported computer chips, steel, oil and natural gas, as well as against copper, pharmaceutical drugs and imports from the European Union — moves that could essentially pit the U.S. against much of the global economy.

It is unclear how the tariffs could affect the business investments that Trump said would happen because of his plans to cut corporate tax rates and remove regulations. Tariffs tend to raise prices for consumers and businesses by making it more expensive to bring in foreign goods.

Trump says 25% tariffs on Canada and Mexico coming on Feb. 1 as he signs several orders on economy

Many voters turned to Trump in the November election on the belief that he could better handle the inflation that spiked under Biden. But inflation expectations are creeping upward in the University of Michigan's index of consumer sentiment as respondents expect prices to rise by 3.3%. That would be higher than the actual 2.9% annual inflation rate in December's consumer price index.

Trump has said that the government should raise more of its revenues from tariffs, as it did before the income tax became part of the Constitution in 1913. He claims, despite economic evidence to the contrary, that the U.S. was at its wealthiest in the 1890s under President William McKinley.

“We were the richest country in the world,” Trump said Friday. “We were a tariff country.”

Trudeau has told Canadians that they could be facing difficult times ahead, but that Ottawa was prepared to respond with retaliatory tariffs if needed and that the U.S. penalties would be self-sabotaging.

Trudeau said Canada is addressing Trump’s calls on border security by implementing a CDN$1.3 billion (US$900 million) border plan that includes helicopters, new canine teams and imaging tools.

Trump still has to get a budget, tax cuts and an increase to the government’s legal borrowing authority through Congress. The outcome of his tariff plans could strengthen his hand or weaken it.

Democrats were quick to say that any inflation going forward was the result of Trump, who is about to start his third week back as president.

Trump takes executive actions on energy, inflation, and tariffs on first day

“You’re worried about grocery prices. Don’s raising prices with his tariffs," Senate Democratic Leader Chuck Schumer of New York posted on X. "You’re worried about tomato prices. Wait till Trump’s Mexico tariffs raise your tomato prices. … You’re worried about car prices. Wait till Trump’s Canada tariffs raise your car prices,” he wrote in a series of posts.