On Thursday, President Trump announced the cessation of trade discussions with Canada, pointing to an advertisement campaign that referenced former President Ronald Reagan’s warnings about the enduring risks associated with tariffs amidst the ongoing trade tensions between the United States and Canada.

In a message on Truth Social, Trump accused Canada of utilizing the advertisement to “interfere” with an impending Supreme Court case that will decide on his power to implement extensive tariffs on foreign nations.

“Tariffs play a crucial role in the national security and economy of the U.S.A. Due to their outrageous actions, ALL TRADE TALKS WITH CANADA ARE NOW TERMINATED,” Trump declared.

Ontario Premier Doug Ford, known for his frequent confrontations with Trump, initiated the ad campaign earlier this month. The advertisement includes a segment from a 1987 speech by Reagan, where he addressed tariffs on Japanese imports at the time and warned about the adverse effects of prolonged trade conflicts on consumers.

“High tariffs inevitably provoke retaliation from other countries, sparking intense trade wars. Then the worst occurs,” Reagan states in the ad. “Markets shrink and collapse, businesses and industries are shuttered, and millions face unemployment.”

In August, Trump had announced a 35 percent tariff on all goods from Canada, though items under the 2020 U.S.-Mexico-Canada trade agreement were not included.

Canada is one of the United States’ top trading partners, and their economies are heavily intertwined when it comes to certain products. But Trump has repeatedly argued the U.S. does not need Canadian goods, and that Canada is far more reliant on America for its economy.

Canadian Prime Minister Mark Carney visited the White House earlier this month, where he and Trump discussed trade. 

“There’s still great love between the two countries, but you know American people want product here, they want to make it here,” Trump said during the meeting. “We are competing for the same business. That’s the problem.”