President Donald Trump is threatening Canada with a 50% tariff on any aircraft sold in the U.S., the latest salvo in his trade war with America’s northern neighbor as his feud with Prime Minister Mark Carney expands.

Carney said he and Trump discussed topics ranging from the Ukraine war to "Arctic security," shorthand for the controversy over Greenland.

Canadian Prime Minister Mark Carney said Thursday he expects the United States to "respect Canadian sovereignty," responding to reports that State Department officials met with separatists from the oil-rich province of Alberta.