The target for 2035 would see emissions slashed by 45 to 50 percent from 2005 levels, on its way to net-zero by mid-century.

But it is only five percent above its previous commitment for 2030.

Both objectives would require a major acceleration of the nation's climate efforts as Ottawa struggles to advance initiatives amid pushback over their costs.

Prime Minister Justin Trudeau's minority Liberal government has faced growing calls from his main rival, Tory leader Pierre Poilievre, to scrap his centrepiece carbon tax.

Polls show Poilievre leading Trudeau by 20 percentage points, and he has been itching for snap elections.

Environment Minister Steven Guilbeault said the 2035 target "keeps us on track to keep the promise to our kids and grandkids that the world we leave behind for them will be safe, sustainable, affordable and prosperous."

In a statement he called the target "realistic and achievable."

But environmental group 350.org said it was "gravely concerned" that the target falls short of what is needed to avoid the worst impacts of the climate crisis, while the Climate Action Network called it "weak".

The Pembina Institute said "Canada's governments and industries must be more ambitious to fully enhance our competitiveness in the new global clean energy economy."

Canada is responsible for less than two percent of global greenhouse gas emissions, but it is one of the highest emitters per capita.

One of the world's top oil and gas producers, Canada has missed all its interim carbon emission targets.

Emissions finally started to fall in recent years. But an audit last month by Canada's environment commissioner, Jerry DeMarco, warned that time was running out to bridge the gap to 2030.

Canada's greenhouse gas emissions have fallen by 7.1 percent from 2005 levels to 708 megatonnes of carbon dioxide equivalent, according to the latest government data.

DeMarco said in November that Ottawa "has not made sufficient progress" to reduce emissions by up to 45 percent from 2005 levels and now has only six years to achieve most of those reductions.

Guilbeault responded, "We have a fair shot at meeting our 2030 target."