TORONTO -- Ontario's governing Liberals forced a new debate on minimum wage and climate change in the legislature on Thursday in an apparent attempt to back the embattled Progressive Conservatives, who are in the middle of a leadership race, into a corner on wedge issues.

Pushing the legislature to revisit the two issues, which are already passed into law, seems equally aimed at seeping support from the New Democrats, said Myer Siemiatycki, a professor of politics at Ryerson University in Toronto.

"I see it at as a political intervention directed at possibly dual targets," Siemiatycki said.

"I think the Liberals are aiming this in part at that fairly significant swath of voters who could go either NDP or Liberal and trying to shore up the perception of the Liberals as the only party that can stand in the way of a Conservative election and the only party that can actually deliver a progressive political agenda," he said.

At the same time, he said, "this is kind of a provocation to require the Conservatives to take a stand that would identify them around some pretty core issues as being opposed to a progressive orientation."

Climate change and minimum wage have both emerged as key issues in the Tory leadership race, with all candidates but ousted leader Patrick Brown coming out against the carbon tax at the crux of the party's platform. The carbon tax, a proposed replacement to the Liberals' cap-and-trade system, would bring an estimated $4 billion and fund an income tax cut and other measures.

The first leadership debate, which took place before Brown announced his candidacy, also saw four candidates vow to halt or slow a planned increase that would push the minimum wage to $15 next year.

The Liberals brought both topics back to the legislature Thursday after their plan to debate proposed legislation targeting Buy American policies in the U.S. was delayed by the Progressive Conservatives.

The Tories have filed motions seeking more details on what the bill would accomplish, saying it doesn't appear to expand the government's powers beyond those it already has.

The two Liberal motions held up for debate as a replacement sought an endorsement for a $15 minimum wage starting in January 2019 and recognition that climate change is a problem that should be tackled through carbon pricing.

The motion on minimum wage was debated in the morning but has not yet been put up to a vote. The motion on climate change was set to be debated in the afternoon.

Liberal House Leader Yasir Naqvi denied trying to stir tensions within the Oppositions, saying both issues are worth revisiting ahead of the June election.

"I think it's a very important debate to have to understand where all members and all political parties stand," Naqvi said.

"We keep hearing different things from different Conservatives in the province about whether they believe in increasing the minimum wage (to $15 an hour) by January 2019 or not. Some believe the minimum wage should just stop at $14, some believe that it should be increased but at a slower pace, some believe that it should be rolled back," he said.

"We are very clear as to how we feel climate change should be dealt with... I think Ontarians deserve to know where do the opposition parties, in particularly the Conservatives, stand. Clearly what we know right now is that they don't even believe in putting any price on pollution," he said.

The Conservatives, meanwhile, said the move is nothing but a political ploy by a government "desperate" to stay in power.

"Even when you look at the chaos within our party, this is a government that's trailing by 25 points in the polls," said Tory legislator Todd Smith.

"They're trying to salvage something, anything, to give them some credibility with voters again and this is what they're choosing to do. It's all politically motivated."