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General Motors’ CAMI assembly plant in Ingersoll, Ont. The company said this week it would end production of the Chevrolet BrightDrop electric parcel van at the plant.Mark Spowart/The Canadian Press

Ottawa’s move to impose tariffs on some vehicles imported by General Motors GM-N and Stellantis NV STLA-N will harm Canada’s manufacturing sector and drive off investments, the Detroit Three automakers say.

The government of Canada on Thursday said it will reduce the number of vehicles the carmakers can import tariff-free, in response to production shifts by the two automakers that could cost thousands of jobs in Ontario. Finance Minister François-Philippe Champagne said on social media the tariffs are a “clear consequence” of the “deeply disappointing” shifts by Stellantis and GM.  

Brian Kingston, president of the Canadian Vehicle Manufacturers’ Association, which represents GM, Stellantis and Ford Motor Company F-N in Canada, called Canada’s retaliation “an unforced error at the worst possible time.”

“We share the government’s goal of protecting Canada’s auto industry and its workers,” Mr. Kingston said. Tariffs on automakers in Canada when they are already under enormous pressure from U.S. trade policies only makes a difficult situation worse, he said.

In response to U.S. President Donald Trump’s 25-per-cent tariffs on imported vehicles, Canada launched a tariff remissions plan for the automakers that assemble cars domestically. The cars these companies import from the U.S. remain tariff-free if the automakers maintain a certain investment footprint in Canada. Details of the agreements are confidential.

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Ottawa determined Stellantis and GM violated the agreements with recent moves: GM ended production of the Chevrolet BrightDrop electric parcel van in Ingersoll, Ont., costing 1,150 jobs; and Stellantis moved planned production of the Jeep Compass to Illinois from Brampton, Ont., where about 3,000 are laid off.

In a letter to GM Canada president Kristian Aquilina, Mr. Champagne also highlighted declining production of the Chevrolet Silverado at GM’s Oshawa plant. GM has been boosting the pickup truck’s output at U.S. plants, he noted in the letter posted online.

Industry Minister Mélanie Joly threatened to sue Stellantis over the Jeep move, which the automaker made as part of a plan to boost U.S. output by 50 per cent over the next four years, adding more than 5,000 jobs in Illinois, Ohio, Michigan and Indiana.

Mr. Kingston said manufacturers facing remissions rules would rather export cars to Canada than build them here and risk being hit with tariffs for making decisions based on changing consumer demands or business requirements.

“This is completely eroding our competitiveness right now for manufacturing,” Mr. Kingston said by phone. “The tariff regime plus the EV mandate, now we have legal threats being levied to companies. It is virtually impossible to imagine a scenario where someone is looking at new investments in Canada under this framework.”

The Stellantis Brampton factory has been idle for almost two years awaiting a retooling to build the Jeep.

Both automakers say the plants are not permanently closed, and are looking at options for other vehicles to build there. 

Ontario is home to plants owned by Ford, General Motors, Stellantis, Honda and Toyota. Ford’s Oakville plant is idle but being retooled to make pickup trucks, the company says.