Wildfire smoke from Canada sparks tariff threats as the president targets pollution crossing into the U.S.

Donald Trump has threatened to impose tariffs on Canada over wildfire smoke that is choking US cities.

The smoke coming from active wildfires in Canada has led to unhealthy air quality in swaths of the U.S., which could affect the World Cup final in New Jersey.

Trump blamed Canada for wildfire smoke and called for more tariffs, accusing the country of mismanaging its forests.