CANADIAN Prime Minister Justin Trudeau faced the biggest test of his political career after Finance Minister Chrystia Freeland, long one of his most powerful and loyal ministers, resigned from the Cabinet on Monday.

The move raised questions about how much longer the prime minister of nearly 10 years — whose popularity has plummeted — can stay on as his administration scrambles to deal with incoming US President-elect Donald Trump.

Mr Trudeau swiftly named ally and close friend Dominic LeBlanc, the public safety minister who recently joined him at dinner with Mr Trump at Mar-a-Lago, to replace Ms Freeland.

After being sworn in, LeBlanc told reporters he and Trudeau are focused on the cost-of-living crisis facing Canadians and on finding common ground with Mr Trump on border security and economic issues.

“It’s not been an easy day,” Mr Trudeau later told a room of party supporters. He called it one of his party’s “toughest days” but he did not say what he planned to do.

Jagmeet Singh, leader of the opposition New Democratic Party, which Justin Trudeau’s ruling Liberals have relied upon to stay in power, called for him to resign earlier on Monday.

The main opposition Conservatives have not called for Mr Trudeau’s resignation, but demand an election.