Trump sends Canada a tariff warning as wildfire smoke smothers US cities ahead of FIFA final match

President Donald Trump is using wildfire smoke from Canada to threaten tariffs. more than 100 million people across the Midwest, Northeast and Mid-Atlantic breathing in dangerous air brought by thick, choking plumes of smoke from wildfires in Canada.

There are nearly 1,000 active fires across Canada as of Saturday, according to its government. So far this summer, about 3,500 fires — including a dozen blazes that flared up in Ontario in recent weeks — have burned more than 6 million acres in the country.

Trump blames Canada for wildfire smoke crisis

Writing on Truth Social on Friday, Trump accused Canada of failing to manage its forests properly, blaming the country directly for the smoke now smothering swathes of the US.

"The United States is being unnecessarily invaded by filthy, polluted, and unhealthy air, the quality of which is dangerous, and totally unacceptable!" he wrote, adding, "The cost is incalculable!"

According to the president, the smoke has become a recurring annual burden that is costing the US billions of dollars, although the basis for that figure was not made clear. He argued that this cost should now be factored into the tariffs already imposed on Canadian goods.

Nearly 1,000 wildfires burning across Canada

Canadian government figures show that almost 1,000 fires are currently active nationwide as of Saturday.

Officials say the overwhelming majority of the roughly 800 active fires are classified as "out of control", and the resulting haze has drifted deep into the US, reaching cities including New York, Chicago and Minneapolis.

Air quality alerts disrupt sport and summer events nationwide

The smoke has forced the cancellation or postponement of a string of high-profile fixtures and gatherings. A baseball match between the Cleveland Guardians and the Pittsburgh Pirates was called off, as was the RowFest National Championships in Michigan.

More than a dozen states remained under air quality alerts as the smoke disrupted summer plans. A baby parade in Flint, Michigan, a rock concert in Herndon, Virginia, and the America's Mile marathon in Pittsburgh were all cancelled on Friday.

The economic toll has extended to businesses during what is usually a lucrative season, with Pennsylvania's Kennywood and Sandcastle Water Park both forced to shut their gates because of poor air quality.

Republicans in Congress push for sanctions on Canada

The smoke has added fresh strain to an already tense relationship between Washington and Ottawa, with several Republican lawmakers now calling for punitive measures against Canada.

Senator Bernie Moreno of Ohio said he intends to introduce legislation next week to sanction Canada and its officials, having shared a post highlighting pollution levels in Cleveland. Representative Nick Langworthy of New York said he was contacting Canadian officials directly to press them into action.

"Canada must take meaningful action to prevent these catastrophic wildfires and protect both Canadians and Americans," Langworthy wrote on X. "If it refuses to do so, there should be consequences."

A group of four Republican representatives from Michigan went further still, writing to Canadian Prime Minister Mark Carney this week demanding a response.

"We are done accepting apologies in place of action. If Canada will not manage its forests to prevent these fires, the United States will look elsewhere, and act on our own, to protect our people," the letter said.

The diplomatic pressure comes on top of existing friction between the two allies over Trump's tariff policy and his repeated suggestion that Canada should become the 51st US state.

Chicago records worst air quality in its history

Some of the country's worst readings were logged in Milwaukee, Chicago and Detroit on Friday morning, while unhealthy pollution levels also pushed into southern Ohio and West Virginia.

"Chicago is currently experiencing its worst air quality in recorded history," the mayor's office said in a social media post on Thursday evening. "Please stay indoors, and if you must go outdoors, use a well-fitted N95 or KN95 mask for your safety."

Detroit's health department began handing out free masks to residents while urging people to remain indoors. In Philadelphia, officials said in a Friday news release that "everyone is likely to experience health effects from being exposed" to the smoke.

In Washington DC, health authorities were distributing masks to government staff working outdoors, the department confirmed, while outdoor pools, spray parks and government-run outdoor activities were all shut down.

Delaware's Department of Natural Resources and Environmental Control forecast unhealthy air for sensitive groups on Saturday, an improvement on Friday, when conditions were rated "very unhealthy" before easing slightly to "unhealthy", according to CNN affiliate WRDE. Even so, visitors, including some of the most vulnerable, still turned out at Rehoboth Beach in Sussex County on Friday.

Will the smoke clear in time for the FIFA World Cup weekend?

Forecasters expect a brief but sharp rainstorm to bring southerly winds that push the smoke northward, clearing the air by Saturday evening. However, winds shifting back from the north could usher in a fresh, if lighter, pulse of smoke by Sunday afternoon.

In New York City, Saturday's storms are expected to bring heavy downpours and a risk of brief flash flooding in low-lying urban areas, though conditions should clear by Sunday morning. That sets up more favourable weather for Sunday afternoon's World Cup match between Argentina and Spain, with temperatures expected in the low 80s Fahrenheit.

Skies are forecast to be largely clear, though some haze may linger higher in the atmosphere from residual smoke. Air quality across the region is expected to gradually improve heading into the new week.