Millions of people in North America have been advised to wear N95 masks outdoors due to poor air quality levels sparked by intense wildfires in Canada.
Millions of Americans in the Midwest and the Northeast are under air-quality alerts as smoke moves south from more than 400 active Canadian wildfires.
A new US-Canada border deal meant to halt the flow of asylum seekers at unofficial border crossings has taken effect.
Last year, nearly 40,000 migrants crossed into Canada at an unofficial border crossing at the end of a remote rural road in upstate New York - a record number - to seek asylum. Many are driven by the belief that the country is more welcoming than the US. But can Canada handle the influx?
Biden's visit is expected to focus heavily on Haiti, where Washington wants Canada to take the lead
The White House has said there is no indication three flying objects blasted out of the sky over the weekend by the US military are linked to alleged Chinese spying.
The US has shot down another unidentified flying object in the fourth military operation of its kind this month.
Nearly 100 million people in Canada and the US brace for some of the coldest air on earth, as a record-breaking deep freeze hits North America.
