Canada's Liberal Party will announce Prime Minister Justin Trudeau's successor on Sunday as both party chief and head of the country's government in the midst of a trade war with the United States that could cripple the Canadian economy.

Carney cast himself during the campaign as an even-keeled political outsider with the economic bona fides to take on Trump and manage a trade war.

The next prime minister and party leader, a former governor of the central banks of Canada and England, will have to deal with the tense relationship with the US