US President Donald Trump has criticized Canada over smoke pollution caused by wildfires that have affected large portions of the United States, and threatened to impose higher tariffs on Canadian goods to offset the costs associated with the haze. Speaking on Truth Social on Friday, Trump described the situation as “Willful Negligence” and a recurring problem that he said was costing the United States billions of dollars. He accused Canadian authorities of failing to properly manage forests through basic maintenance such as brush and debris removal, which he linked to the scale of the current fires. Trump also announced plans to contact Canadian Prime Minister Mark Carney to discuss possible responses to the ongoing smoke pollution.

The wildfire smoke has led to unhealthy air quality alerts across the US Midwest and Northeast, with cities including Detroit, Chicago, Washington, New York, and Boston significantly impacted. Detroit was reported as the most polluted city globally on Friday, according to Air Quality monitoring. The smoke also reduced visibility in New York City and caused concerns about the upcoming World Cup final scheduled for Sunday in New Jersey, though meteorologists suggested conditions might improve by game day. Officials emphasized ongoing monitoring of the air quality situation, while some residents in affected areas wore masks outdoors and distributed free masks in public spaces such as libraries and train stations.

Canada’s emergency management minister Eleanor Olszewski responded by highlighting ongoing cooperation between the two countries in combating wildfires, emphasizing the “long history of working together.” She noted that Canada had invested approximately $12 billion in forest sustainability and fire prevention efforts since 2020. Ontario, which has been one of the hardest-hit regions, reported a worsening wildfire situation with several remote communities evacuated. Authorities continue to deploy dozens of aircraft to fight the blazes. In addition, 16 active fires were burning in the Superior National Forest on the Minnesota-Canada border.

The wildfire situation has raised broader questions about causes and responsibilities. While President Trump attributed the fires partly to Canada’s forest management practices, many scientists link the increasing frequency and intensity of wildfires in North America primarily to climate change. Ontario Premier Doug Ford urged a cooperative stance, stating that instead of complaints, political leaders should offer assistance, noting Canada’s reciprocal support to the US during similar crises.

Meteorologists forecast that winds over the Great Lakes region could push more smoke into the Northeast in the short term, though some improvement is expected over the weekend. The presence of fine particulate pollution from the wildfires has raised health concerns due to its particular impact on lung function, distinguishing it from typical vehicle emissions that more heavily affect cardiovascular health.

The cross-border nature of the wildfire smoke highlights the complexity of managing environmental disasters in closely linked regions, reflecting ongoing challenges around climate resilience and international cooperation.