Trump blames Canada for wildfire smoke, says he’ll add cost to tariffs

US President Donald Trump on Friday blamed Canada for wildfire smoke spreading across the United States and said he would add the “incalculable cost” ‌of dealing with the pollution to existing tariffs on Canadian goods.

Heavy smoke from hundreds of Canadian fires enveloped a swathe of the US from the Midwest to the Northeast on Thursday and Friday, prompting warnings to residents to stay indoors.

Detroit on Friday remained the most polluted city in the world, according to tracker IQAir. Washington and Chicago were not far behind, and officials warned against spending unnecessary time outside.

In New York and neighbouring New Jersey, where the World Cup football final will be played on Sunday in an open stadium, the metro area was experiencing air that could be unhealthy for sensitive groups, an improvement after smog on Thursday made the Manhattan skyline barely visible.

But the National Weather Service (NWS) warned the smoke may thicken overnight into Saturday morning.

Tournament organisers are “monitoring closely”, White House World Cup task force executive director Andrew Giuliani told a briefing.