US President Donald Trump accused Canada of playing "dirty" amid an escalating dispute over an advertisement featuring former leader Ronald Reagan — a controversy that led Trump to cancel planned trade talks between the two countries.

The Canadian province of Ontario said it would pull the offending anti-tariff ad on Monday so that negotiations could restart, after Trump alleged that the ad misrepresented the views of fellow Republican Reagan.

But Trump showed no sign of backing down, saying Ontario should not have let it air during the first two games this weekend of baseball's World Series.

Adding extra spice to the row, the World Series features a Canadian team, the Toronto Blue Jays, facing a US team, the Los Angeles Dodgers. The Blue Jays thrashed the Dodgers 11-4 in the first game on Friday.

"Canada got caught cheating on a commercial, can you believe it?" Trump told reporters before heading on a trip to Asia.

"And I heard they were pulling the ad — I didn't know they were putting it on a little bit more. They could have pulled it tonight," Trump added.

After a reporter said the ad would be pulled on Monday, Trump replied: "That's dirty play. But I can play dirtier than they can."

Trump announced on his Truth Social network on Thursday that he had "terminated" all negotiations with Canada over what he called the "fake" ad campaign.

Less than 24 hours later, Ontario premier Doug Ford said he was suspending the ads after talking to Canadian Prime Minister Mark Carney about the spiralling row with Washington.

"In speaking with Prime Minister Carney, Ontario will pause its US advertising campaign effective Monday so that trade talks can resume," Ford said in a post on X.