Montreal, Canada – Canadian Prime Minister Justin Trudeau says he has “a lot of work” to do to regain the confidence of Canadians after his Liberal Party’s defeat in a special parliamentary election in the city of Montreal.

The Quebec nationalist Bloc Quebecois won the vote on Monday — known as a by-election — in the electoral district of Lasalle-Emard-Verdun, which had been a longtime Liberal stronghold.

Experts said the by-election was a “litmus test” for the Liberals before the next Canadian general election, which is set to take place before the end of October 2025 and appears likely to end nearly a decade of Liberal governments.

Speaking to reporters in Ottawa on Tuesday, Trudeau was asked whether his leadership was weakened after the loss.

“Obviously, it’s never fun to come so close and not win a by-election. But we know that we have a lot of work to do to regain the confidence of people in LaSalle and people across the country who are concerned about the situation they’re in,” Trudeau said in French.

“We have a lot of work to do, and we’ll continue to do it.”

The Bloc’s Louis-Philippe Sauve won the by-election with 28 percent support, according to the official results, narrowly defeating the Liberals’ Laura Palestini, who secured 27.2 percent of the vote.

Campaign pamphlets for the leading candidates in the Montreal by-election [Jillian Kestler-D’Amours/Al Jazeera]

Monday’s contest came at a tumultuous time in Canadian federal politics — and for the Trudeau-led Liberals in particular.

Parliament resumed this week, just days after the left-leaning New Democratic Party (NDP) announced its abrupt withdrawal from a 2022 agreement to prop up Trudeau’s minority government.

The move means the Liberals are more vulnerable if a no-confidence vote is triggered in the House of Commons, and the result of that vote could force Trudeau to call early elections.

The prime minister, who has been in power since 2015, has seen his popularity plummet amid soaring costs of living and a deepening housing crisis. Recent polls show Trudeau and the Liberal Party far behind the opposition Conservative Party of Canada.

And that dwindling public support has spurred discontent from members of Trudeau’s own party, including after the Liberals lost another longtime seat in a widely watched Toronto by-election in June.

Speaking to Al Jazeera before Monday’s vote in Montreal, Stewart Prest, a political science lecturer at the University of British Columbia, said a Liberal defeat would give “fresh ammunition to those who are saying it’s time for a significant change in the Liberal Party”.

And that, Prest said, would “inevitably turn to the question of whether Justin Trudeau should continue to stay on as leader”.

So far, Trudeau has said he plans to stay on as head of the party for the next election.

Asked on Tuesday if the by-election loss puts his leadership in question, Trudeau replied: “We have a lot of work to do, but I continue to do the work.”