US President Donald Trump has said Canadian Prime Minister Mark Carney should "pay some damages" over wildfire smoke drifting across the border into the United States, claiming that American air had been "poisoned" as a result. The remarks add another point of friction to the already strained relationship between Washington and Ottawa, which has recently been dominated by disputes over tariffs.

Full details of the exchange were not available beyond Trump's comments, which were made amid broader tensions between the two governments over trade. The wildfire smoke issue reflects a recurring seasonal problem, as blazes in Canada have periodically sent smoke southward, affecting air quality in parts of the US.