Trudeau resigning as Liberal leader

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• Chrystia Freeland pegged by some Liberal MPs as Justin Trudeau's successor if he resigns

His decision will set off a competitive leadership race to replace him and find a contender to take on the Liberals' key rival, Conservative Leader Pierre Poilievre, in the next federal election. 

Trudeau has been under mounting pressure to resign amid sinking public opinion polling, including from his own caucus. 

At least two dozen individual MPs and several regional caucuses — including Atlantic Canada, Quebec and Ontario — have called for him to step down since before the holiday break.

His political future was put into a tailspin when Chrystia Freeland, long seen as his top lieutenant, resigned as finance minister and deputy prime minister last month, the day she was scheduled to present the fall economic statement.

Conservatives threaten non-confidence motion

In a letter to Trudeau that was subsequently posted to social media, Freeland said she had no choice but to resign after Trudeau approached her about moving her to another cabinet role.

Freeland also took a jab at Trudeau's handling of the economy, denouncing what she called the government's "costly political gimmicks" and imploring him to work collaboratively with the country's premiers to take on U.S. president-elect Donald Trump's tariffs threat.

She went on to write that she and Trudeau have been "at odds" in recent weeks about how to handle the incoming U.S. administration.

The Conservatives, which have been riding high in the polls for more than a year, have promised to move a motion of non-confidence in the Liberal government as soon as possible in the new year.