President Trump's 50% tariff on roughly $20 billion in Canadian products took effect early Saturday after eleventh-hour negotiations between Washington and Ottawa fell apart, with each side blaming the other for the breakdown.
U.S. Trade Representative Jamieson Greer told reporters that Canada walked away from a deal the two sides had sketched out earlier in the week. The tariff, imposed under Section 338 of the Tariff Act of 1930, a Depression-era law that had never been invoked before, covers a broad range of Canadian goods while exempting energy, fish, and critical minerals. Trump had originally set a 12:01 a.m. Wednesday deadline, then pushed it back three days to give negotiators more room. The extra time was not enough.
Canadian Prime Minister Mark Carney fired back within hours, vowing to match the new duties dollar for dollar and promising additional government support for Canadian workers and businesses on top of nearly $25 billion Ottawa says it has already spent over the past 18 months.
Greer laid the collapse squarely at Ottawa's feet. In a statement first posted by reporter Mike LeCouteur, Greer said Canada had been offered terms more favorable than those extended to any other major exporter:
"Tonight, Canada declined to finalize the trade deal under the terms agreed earlier this week, despite the US offer to Canada to receive the best treatment of any major exporter to our market."
He added that "new demands and walk backs of other commitments by Canada have upended the careful balance reached in the past days." Greer did not specify which Canadian demands derailed the agreement, and the precise terms of the framework remain undisclosed.
The trade representative had signaled the administration's posture days earlier. "If a country retaliates against us, we're obviously not going to tolerate that," Greer said last week. "My sense is the Canadians, they want to have a more conciliatory approach, but we'll see."
That warning carried weight. Canada and China are the only two countries that imposed retaliatory tariffs after Trump levied sweeping, double-digit duties on virtually every country last year, declaring the U.S. trade deficit a national emergency. Ottawa's retaliation included bans on American liquor and duties on American automobiles, moves the Trump administration had been pressing Canada to reverse as a condition of any new agreement.
Ottawa told a different story. Carney attributed the breakdown to "last-minute changes in the US proposed terms" that he called "unfair, uneconomic, and called into question the reliability of any deal." He framed the tariffs as part of a broader American shift away from traditional alliances:
"We have recognised from the beginning that America has changed, and that we will not return to our old relationship. Our government understood, before many, that America is altering all its trade relationships. Putting tariffs on its closest allies and charging for access to its vast market."
Carney promised swift retaliation. "Canada will match those tariffs dollar for dollar to protect our workers and businesses," he said, adding that his government would introduce unspecified additional measures in the coming days.
The rhetoric was notably sharper than what Canadian officials had offered just days earlier. On Friday, four hours before the final deadline, Canada's Minister of Internal Trade, Dominic LeBlanc, emerged from Greer's office and struck a cautiously hopeful tone. "We have more work to do," LeBlanc told reporters. "We are going to continue working up until the last minute. Our job is not finished."
An email from LeBlanc's office to Carney's U.S. economic advisory team, obtained by Reuters, described the talks as "complex and consequential." The email read, in part: "I want to be direct with you about where we stand. This is an intense moment. The stakes are significant... That pressure is being felt by Canadians across the country, and those at the table are acutely aware of it."
The legal foundation matters. After the Supreme Court struck down Trump's "Liberation Day" tariffs in February 2026, ruling that the International Emergency Economic Powers Act did not authorize them, the administration turned to Section 338 of the Tariff Act of 1930. The statute lets the president impose tariffs of up to 50 percent on imports from countries that have discriminated against American businesses. It requires no formal trade investigation, and it sets no time limit on how long the tariffs can remain in place.
The administration argues Canada's retaliatory measures, the liquor bans, the auto duties, constitute exactly the kind of discrimination Section 338 was designed to address. The Office of the U.S. Trade Representative reported that the U.S. goods trade deficit with Canada stood at $46.4 billion in 2025, and the administration has pointed to what it calls discrimination against American exports of cars, alcohol, and cheese.
Canada is America's second-largest trade partner. Nearly 72 percent of Canada's goods exports last year went to the United States, which means Ottawa has far more to lose from a prolonged tariff standoff than Washington does. That asymmetry is the core of the administration's leverage, and the reason Carney's government has spent $25 billion trying to cushion the blow for its own workers.
Trump himself seemed optimistic through much of the week. On Monday, he spoke with Carney by phone about a potential deal. On Wednesday, when he announced the three-day extension, he told reporters at Joint Base Andrews: "The deal with Canada is moving along and we should be able to have a deal." He added: "I only make good deals. Much better deal for the United States, both with Canada and Mexico."
That same day, Trump teased a possible revival of the Keystone XL pipeline, the cross-border energy project canceled under the Biden administration, as a potential element of a broader agreement. "The great Keystone XL Pipeline, long ago killed by Sleepy Joe Biden, may be awoken from the grave!" Trump posted on Truth Social. He also said the administration was "starting on a new deal with Mexico," though details remain unclear.
The two leaders' public rapport had seemed warm enough. Last month, Trump and Carney were spotted chatting at the World Cup final in New Jersey, shortly before the 50 percent tariff was unveiled. Carney, speaking to the Associated Press earlier in the week, described the negotiations as "very intense and delicate" and said it was "not the time to talk about negotiations in public."
Behind the scenes, the gap proved too wide. Reuters reported that Canada had been pressing Washington to cut the tariff on Canadian-built vehicles to 15 percent from 25 percent and to halve the levy on Canadian steel and aluminum to 25 percent. Politico also reported Canada was pushing for lower tariffs on automobiles and other goods. Whether those requests were among the "new demands" Greer cited is not clear from either side's public statements.
The collapse leaves the U.S.-Canada trade relationship in its most strained condition in decades. A 50 percent tariff on $20 billion in goods, covering products from wine to cement to hockey sticks, is not a negotiating flourish. It is a concrete cost that will ripple through supply chains on both sides of the border.
Section 338 gives the administration staying power that the struck-down IEEPA tariffs lacked. No investigation is required. No sunset clause forces a renegotiation. The tariffs can remain in place as long as the president determines that Canada is discriminating against American commerce. That open-ended authority changes the calculus for Ottawa, which cannot simply wait out a legal challenge the way it might have with the earlier round.
Carney's pledge to match the tariffs "dollar for dollar" guarantees escalation in the short term. But the underlying math favors the larger economy. When nearly three-quarters of your exports go to a single country, retaliatory tariffs are a weapon that cuts the hand holding it. Even within the Republican Party, trade policy has drawn debate over how tariffs affect American producers, but the case for holding firm against a trading partner that retaliated first, and refused the most favorable terms offered to any major exporter, is straightforward.
Several questions remain unanswered. What specific demands did Canada introduce that broke the deal? What were the precise terms of the framework Greer says Ottawa walked away from? And what "additional measures" is Carney preparing? Neither side has offered those details, and the political calendar in Washington will only increase the pressure to resolve the standoff, or harden positions further.
Canada had a deal on the table that Greer called the best terms offered to any major exporter. Ottawa chose to walk. Now Canadian workers and businesses get to live with the consequences of that choice.
