Trump threatened once again to turn the key economic relationship between the United States and its second-biggest trading partner topsy-turvy.

President Donald Trump says he plans to hike tariffs on imports of Canadian goods by an extra 10% because of an anti-tariff television ad aired by the province of Ontario.

Trump announces a 10% tariff increase on Canada, citing a misleading Ontario ad as justification for the decision.

Trump threatened once again to turn the key economic relationship between the United States and its second-biggest trading partner topsy-turvy.