Prime Minister Mark Carney said on Tuesday that Canada would use “all powers that we have” to pursue Stelco’s American owner “to the fullest extent of the law” over hundreds of planned layoffs in Hamilton, Ont.

Stelco, based in Hamilton and owned by Cleveland-Cliffs of Ohio, said on Monday it would cut up to 500 jobs, tying the decision directly to President Trump’s trade war with Canada. The Trump administration imposed 50 percent tariffs on foreign steel last year under Section 232 of the Trade Expansion Act, and Canada answered with duties on many American-made steel products.

Speaking at a news conference in Vancouver, Mr. Carney singled out the company’s chief executive, Lourenco Goncalves, for “applauding” the tariffs on Canadian steel imports to the United States. He said he was “very disappointed” by the decision to lay off workers.

“Our thoughts are with the workers and the families who have been betrayed by the company,” the prime minister said. “The company made representations, and has legal obligations for employment. We intend to use all powers that we have, and pursue them to the fullest extent of the law.”

Mr. Carney said there is “money on the table from the federal government” to help companies like Stelco blunt the impact of the trade war. In an email to CBC News on Monday, a Cleveland-Cliffs spokeswoman confirmed that Industry Minister Mélanie Joly had been in touch with Mr. Goncalves about financial support.

The spokeswoman, Pat Persico, the company’s senior director of corporate communications, said that while Stelco is idling some operations in Hamilton, the company expects “a significant number of workers” will be absorbed by its Lake Erie Works in Nanticoke, Ont. She did not say how many.

In a memo to employees obtained by CBC News, Frederic Fafard, Stelco’s vice-president of sales, called the cuts “an unfortunate but necessary action to help ensure the survival of Stelco in what has become a challenging and unsustainable market.”

Cleveland-Cliffs bought Stelco in a $3.4-billion Canadian cash-and-stock deal that closed in November 2024. In the news release announcing the transaction, Alan Kestenbaum, Stelco’s chief executive at the time, said it “keeps national interests at the forefront and recognizes the importance of the workforce.”

Cleveland-Cliffs did not immediately respond to a request for comment on Wednesday about Mr. Carney’s mention of possible legal action.