Trump Blames Canada for Wildfire Smoke, Threatens to Add Pollution Costs to Tariffs

US President Donald Trump has blamed Canada for the wildfire smoke spreading across large parts of the United States and threatened to add what he described as the “incalculable cost” of dealing with the pollution to tariffs imposed on Canadian goods.

Heavy smoke from hundreds of wildfires in Canada spread across the US Midwest and Northeast on Thursday and Friday, prompting health warnings and advice for residents to remain indoors as air quality deteriorated.

Trump, who has maintained a tense relationship with Canadian Prime Minister Mark Carney, said he planned to contact the Canadian leader to ask what action his government intended to take.

In a post on Truth Social, Trump accused Canada of failing to properly maintain its forests and said the US was being affected by “filthy, polluted, and unhealthy air”. He argued that the costs linked to the pollution should be reflected in the tariffs Canada pays on exports to the US.

Climate scientists, however, have linked the increasing frequency and severity of wildfires to rising temperatures and increasingly dry conditions. Mike Flannigan, a professor of wildland fire at Thompson Rivers University in British Columbia, said warmer conditions were creating hotter, drier and windier weather that made fires more likely to spread.

Trump imposed tariffs on several major Canadian imports shortly after returning to office in 2025. Carney’s office did not immediately respond to Trump’s latest comments.

The Canadian prime minister said on Thursday that the US could do more to address climate change, which is contributing to warmer and more extreme weather conditions around the world. The two leaders are expected to meet at the FIFA World Cup final in New Jersey on Sunday.

Ontario has been among the Canadian provinces most affected by the latest fires. Many of the blazes are concentrated in remote areas of the province’s northwest, where aircraft are often the only practical means of transportation. Around 650,000 acres, or 2,630 square kilometres, have burned so far this year, compared with about 600,000 acres during the same period last year.

Thousands of people have been forced to evacuate their homes. Namaygoosisagagun First Nation, also known as Collins First Nation, was destroyed by fire, according to community officials. Residents were evacuated by boat and moved to Thunder Bay.

The city is now operating at full capacity as it shelters wildfire evacuees from across northwestern Ontario, Mayor Ken Boshcoff said.

Ontario Premier Doug Ford announced plans to purchase 11 new aircraft to help fight the fires and rejected criticism from US politicians over the province’s response.

The US is also experiencing an above-average wildfire season. According to the National Interagency Fire Center, about 3.7 million acres have burned in the country so far in 2026, compared with a 10-year average of 2.7 million acres.