Conservative Leader Pierre Poilievre's latest unsuccessful attempt to call on Prime Minister Justin Trudeau to repeal his carbon pricing system has secured the support of one Liberal MP.

On Wednesday, Liberal MP for Avalon, Nfld. Ken McDonald was the only member of his caucus to vote in favour on a non-binding motion from the Official Opposition.

While the proposal was defeated in a 209-119 vote, McDonald was the only member of the Liberal, Bloc Quebecois or NDP caucuses who sided with Poilievre's proposal.

The , debated last Thursday, called out the other parties for their support for increasing the price on carbon, while imploring the House of Commons to "call on the government to introduce legislation, within seven days of this motion being adopted, to repeal all carbon taxes."

When McDonald rose in the House to vote in favour of the motion, he was greeted by loud applause and cheers from across the aisle.

This was not the first time McDonald was the only Liberal MP to support a motion touting the Conservatives' pledge to "axe the tax."

In 2022, on their ask for the federal Liberal government to heed Liberal Premier of Newfoundland and Labrador Andrew Furey's request for a carbon tax exemption on home heating fuels.

Poilievre and Trudeau exchanged jabs over the division.

"This carbon tax is not worth the cost. And it's not just me saying it. The Liberal member for Avalon has said, and I quote, 'We are punishing rural areas of our country and the most vulnerable people in society.' Other Liberal MPs like to go back to Atlantic Canada and say they disagree with the prime minister's plan to quadruple the carbon tax to 61 cents a litre. Unfortunately, they lose their spines when they get to the House of Commons," Poilievre said.

"So will he stop bullying them, let them have a free vote, so that we can pass our motion to axe the tax and bring home lower prices?"

After previously shooting back that the Liberal plan is "above and before everything else, a plan on affordability," Trudeau spoke about the conversations he had with Atlantic Canadians over the summer who were devastated by the impacts of extreme weather events.

"They see the impact of climate change and they know that we need to continue to fight climate change while putting money back in their pockets. That's exactly what a price on pollution does. That's what we're going continue to do," Trudeau said.

Since becoming leader, Poilievre has appeared to adopt a strategy of often using his allotted opposition days to advance motions calling for an end to Trudeau's federal fuel charge, allowing him to rack up a tally of how many times the other parties have rejected the idea.