Five federal party leaders jousted over health and child care, the environment and Quebec identity politics in the first of two official election debates Wednesday evening as they sought to sway francophone voters before election day on Sept. 20.

With under two weeks to go, millions of voters were expected to tune in to the two-hour French-language debate and then the English-language debate Thursday night.

They come as opinion polls suggest the Liberals and Conservatives are stuck in a tight two-way race, with the NDP and Bloc poised to determine which of the two main parties emerges victorious.

Liberal Leader Justin Trudeau, Conservative Leader Erin O'Toole, NDP Leader Jagmeet Singh, Bloc Québécois Leader Yves-François Blanchet and Green Party Leader Annamie Paul took part in the Wednesday debate and will convene again Thursday night at 9 p.m. eastern time.

People's Party of Canada Leader Maxime Bernier did not meet the criteria established by the independent Leaders' Debates Commission for participation.

Organized by consortiums of broadcasters, both debates are being held at the Canadian Museum of History — its grand hall transformed into a television studio — in Gatineau, Que., just across the river from Parliament Hill.

The topics discussed Wednesday included climate change, the COVID-19 pandemic and Indigenous Peoples and cultural identity.

The spiciest exchange, however, concerned issues of Quebec identity and representation when an animated Trudeau turned on Blanchet late in the debate.

“You keep forgetting: I’m a Quebecer, I’m a proud Quebecer, I have always been a Quebecer, I will always be a Quebecer," Trudeau said, his face flushed, while a small smile slid across Blanchet's.

"You do not have a monopoly over Quebec … You take the Quebec government’s record as if it’s your own," Trudeau continued. "You have no right to consider me not a Quebecer."

Trudeau, Blanchet clash as leaders spar on health care, environment in #FrenchDebate. #ItsOurVote #CdnPoli #Elxn44

Blanchet conceded to reporters in English after the debate that it was "probably true" that Trudeau was as much a Quebecer as him.

"But in terms of institutions, this is the Assemblée nationale du Québec which speaks for Quebec," he said, referring to the French name for the provincial legislature.

Trudeau also disputed that point, saying the notion that believing in federalism rather than independence means one is not a Quebecer is "irresponsible" and "false."

Quebecers are "obviously not" a monolithic block, Blanchet added in French.

Much of the back-and-forth Wednesday revolved around health care and how to pay for it. Moderator Patrice Roy pushed the politicians to spell out how much money they would give the provinces, and whether they would hand over the extra $28 billion in annual funding requested by premiers.

Trudeau pledged an added $25 billion, but "not unconditionally," while O'Toole reiterated his plan to boost health transfers to the provinces by $60 billion over 10 years, "without conditions because it is a matter of respect" — a word he used repeatedly when referring to Quebec.

"I trust the government of Quebec. Why does Mr. Trudeau always interfere in provincial jurisdiction?" O'Toole asked.

However, freshly released costing for the Conservative platform states that only $3.6 billion of that would come in the first five years.

“I will increase health transfers in a way that’s stable, predictable," O'Toole said.

Trudeau parried that the Tory leader is "not standing up against a two-tier system."

Asked whether vaccination against COVID-19 should be mandatory, Trudeau called the discussion a "false debate" and sought to drive a wedge between his stance and O'Toole's. The Tory leader's position suggests vaccination and rapid testing are equivalent, Trudeau claimed.

“This isn’t the time to be dividing people. We need to work together," O'Toole rebutted, stressing that vaccination is "essential" but that rapid testing, masks and physical distancing also play a role.

The leaders also made their respective pitches for a greener Canada at the end of a summer that has seen fatal heat waves and wildfires.

Pressed on the fate of the Trans Mountain pipeline, which Ottawa bought from Kinder Morgan in 2018, under a would-be NDP government, Singh insisted he opposed the project but gave no definitive answer on what he would do with it as prime minister: “We will take stock of the situation.”

Trudeau said Indigenous communities hope to buy the pipeline and could continue to operate it until "we don't need it."

O'Toole stressed that families in Western Canada have a right to economic recovery, while Paul said it should be cancelled. Blanchet, in line with his belief in greater provincial independence, favours handing money from the crude-oil conduit to Alberta to help fund its energy transition.

As the debate wore on, a few dozen protesters, some carrying PPC signs, continued to mingle on the sidewalk but found themselves blocked from coming near the entrance to the museum.

The Conservatives released the costing for their election platform just hours before the leaders began to arrive at the debate venue Wednesday evening, amid mounting criticism from Trudeau over O'Toole's failure to produce the balance sheet for his plan.

Tory platform pledges would add $30 billion to this fiscal year's forecasted budget deficit of $138.2 billion, according to the document, which is based on the parliamentary budget officer's election platform costing baseline. The deficit would then fall substantially each year thereafter, landing at $24.7 billion in 2025-26.

Blanchet threw a pre-debate punch, telling reporters an hour before game time that the billions in child-care funding pledged to Quebec by the Liberal government fails to show up in the Conservatives' five-year plan.

Conservative officials said Wednesday that an O'Toole government would honour the funding deals with provinces for the first year. But after that the Liberal child-care plan — including $6 billion earmarked for Quebec — would be replaced by the Conservatives' promise to convert the existing child-care expense deduction into a refundable tax credit that would cover up to 75 per cent of child-care costs for low-income families.

"Mr. O'Toole does not even understand the daycare system in Quebec," Trudeau said, noting that the most vulnerable Quebecers do not pay fees and so would not benefit from the credit.

“The Conservative plan … is $6 billion less in the pockets of the Quebec government,” Blanchet added.

O'Toole reiterated that he will "always respect provincial jurisdiction … We will help all families immediately."

Paul said after the debate that daycare has languished below the radar in part because it's framed as a women's issue, further upping the need to bring more women and other-under-represented groups into leadership roles.

"When I talk about bringing more diversity to politics, this is exactly what I mean," she said.

This report by The Canadian Press was first published Sept. 8, 2021.

— With files from Paola Loriggio and Stephanie Taylor