WASHINGTON/MONTREAL – Claiming “their products aren’t good enough,” U.S. President Donald Trump on Monday threatened to block Canadian business jet maker Bombardier from selling airplanes in the country unless the aircraft are built in America.

Trump’s Truth Social post came amid a deteriorating trade war, with Canadian retaliatory tariffs due to go into effect Tuesday.

Quebec-based Bombardier is a key player in the U.S. business aviation market, the world’s largest. It also operates a specialty defense-related manufacturing facility in Kansas and service centers across the country, employing thousands of Americans.

Quebec defends Bombardier

Quebec Premier Christine Fréchette wrote on X that she “will not respond to provocation with provocation.”

She called Bombardier “a source of pride for Quebec” and noted that the company employs thousands of Quebecers.

She added that she had reached out to Bombardier CEO Éric Martel to offer him support.

“Quebec will not allow anyone to dictate where our companies must produce in order to access a market,” Fréchette wrote. “We will defend our companies, our workers, and our expertise with resolve.”

Bombardier said in a statement late Monday that it employs thousands of Americans and supports tens of thousands of U.S. jobs through its operations and supply chain.

The company spends more than $2.5 billion annually with U.S. suppliers, making it a significant contributor to the American aerospace industry, the company said.

“Bombardier values its great partnership with American companies and its U.S. employees,” the statement continued. “Our plan is to continue to invest in our people, our customers and the communities in which we operate across the country.

It was not immediately clear how Trump could enforce a sales ban as the aerospace industry is highly integrated.