Canada's Trudeau on the brink after chaotic day in Ottawa

Canadian Prime Minister Justin Trudeau's government has been thrown into disarray with the abrupt departure of his finance minister, Chrystia Freeland.

By the end of a frenetic day on Monday, a new finance minister was in place - but Canadians had yet to hear directly from Trudeau as questions about his political future reached a fever pitch.

The dramatic departure of the long-time Trudeau ally, coming with the public release of her scathing resignation letter, brought fresh uncertainty to the nation's capital, which was already dealing with major concerns over Donald Trump's tariff threat.

The president-elect has said he would impose a levy of 25% on imported Canadian goods after his inauguration in January unless the shared border was made more secure.

If implemented, the tariffs could have a devastating effect on the country's economy.

• Trump tariff threat puts a strain on Canada-Mexico ties
• Trump takes jab at 'governor' Trudeau

Freeland's sudden exit "just makes Canada look quite confused and uncertain", Chris Sands, director of the Wilson Center's Canada Institute, told the BBC.

"Trudeau finds himself a little bit alone, not super close to any of his ministers, with the big, talented ones mostly now having left," he added.

In her letter, Freeland accused Trudeau of choosing "costly political gimmicks" over addressing the threat posed by Trump's "aggressive economic nationalism".

She said her decision came after Trudeau told her last week that he no longer wanted her to be the government's top economic adviser.

Her departure blindsided the government, leaving the fate of a scheduled economic update in the air for hours and bringing Trudeau and his shaky minority Liberals to the brink.

Mr Sands said Trump's win in November's US presidential election has caused a split among US allies, including Canada.

"Do you respond to Trump by pushing back and standing firm, or do you respond by trying to find a way to avoid conflict?" he said.

Trudeau has made overtures to Trump, including flying to Mar-a-Lago, the president-elect's Florida estate, last month to dine with the president-elect.

But Freeland's perspective, said Mr Sands, was closer to that of Mexico - also facing a tariff threat - and Mexican President Claudia Sheinbaum.

Mexico has positioned itself under the idea that "now is the time to say no, to push back, to take a fighting stance", he said.

Many politicians remember the challenges they faced during Trump's first term in office, he added.

"He hasn't been inaugurated yet, but people are already reacting as though he was the president and taking serious measures."

Freeland, who also served as deputy prime minister, had been Ottawa's lead during the first Trump administration in the successful re-negotiation of the US-Canada-Mexico free trade pact.

It was "a really stressful and overwhelming process for Canada", Mr Sands said.

On Monday, Canada's three opposition party leaders said Trudeau must go.

Pierre Poilievre, leader of the opposition Conservative Party of Canada, called for a federal election as soon as possible.

"Everything is spiralling out of control. We simply cannot go on like this," he said.

Canada's next federal election must be held in October, at the latest.

Laura Stephenson, chair of the political science department at Western University, told the BBC it's not clear that a change in leadership will affect the current US-Canada dynamic.

"I have no confidence that Trump will react any differently to Poilievre than he does to Trudeau," she said, referencing the leader of the Conservative party.

After nine years in power, Trudeau has faced growing calls to resign over concerns he is a drag on his party's fortunes.

The Liberal leader's approval rate has plummeted from 63% when he was first elected to 28% in June of this year, according to one poll tracker.

Opinion polls also suggest the Liberals could face a devastating loss to the Conservatives if an election were held today.

Some Liberal members of parliament have been pressuring Trudeau for months to step down, amid both the grim poll numbers and a series of special election losses in once-safe Liberal seats.

"There's still a number of our members who think we need a change in leadership and I'm one of them," Chad Collins, a Liberal MP, said on Monday evening following an emergency party caucus meeting.

Many other members brushed passed reporters, while some said they remained focused on working for Canadians.

Trudeau did not take questions on his way to a party fundraiser, but he told the crowd he was "damn proud" of his government's accomplishments.

In brief remarks, he said working for Canadian values was "at the core of what makes us Liberals".

"That's why we show up here, even on the toughest days as a party."

Trudeau has defied previous calls to step aside and has said repeatedly that he plans to run in the next federal election.

Also on Monday, the leaders of Canada's provinces and territories met in Toronto to address Trump's tariff threat.

"It's chaos right now up in Ottawa", said Ontario Premier Doug Ford.

Ford said the premiers will "make sure that we tell the world there is stability here, there is certainty here in Canada".