Canada is formally withdrawing from the Kyoto Protocol on climate change, abandoning the world's only legally binding plan to tackle global warming.

Environment Minister Peter Kent confirmed the decision on Parliament Hill just hours after returning from a United Nations climate conference in Durban at which he repeatedly avoided questions about Canada's commitment to the protocol.

Mr. Kent said staying in Kyoto would force Canada to spend about $14-billion buying carbon credits abroad because the country is so far behind in meeting its targets. He blamed the previous Liberal government, saying it agreed to targets without a plan to achieve them.

Story continues below advertisement

"Kyoto, for Canada, is in the past," he said, confirming that the government would invoke its legal right to withdraw from the agreement. He predicted other countries will follow suit.

"It's really only the Europeans who are staying with Kyoto," he said.

Prime Minister Stephen Harper has made no secret of his disdain for the Kyoto Protocol, arguing that a legally binding deal that fails to include the world's two largest greenhouse gas emitters – China and the United States – would hurt Canada's competitiveness and prove ineffective at reducing global emissions. Mr. Kent said he remains hopeful that world leaders will agree on a new legally binding deal under the UN umbrella that includes the largest emitters.

The Kyoto Protocol came into force in 2005, and Canada committed to reducing its greenhouse gas emissions to 6 per cent below 1990 levels during the period of 2008 to 2012. However, recent estimates indicate Canada's emissions are more than 30 per cent above that target.

Environmentalists and opposition MPs rejected Mr. Kent's "apocalyptic" language and said Canada's reputation has been damaged by its role in disrupting other countries' efforts to approve a second phase for Kyoto.

Alberta School of Business professor Andrew Leach said complying with Kyoto purely by buying credits would likely cost even more than Mr. Kent's estimate, because prices would rise.

However, Canada could have avoided paying anything by simply agreeing to more onerous targets in a second round, he said.

Story continues below advertisement

"There isn't a mechanism under Kyoto where Canada could be fined," he said in an interview. Dr. Leach also said Canada could ultimately avoid an explicit finding of non-compliance under the protocol by filing formal notice before the end of this month.

NDP and Liberal MPs noted that the Conservatives have been in office since 2006 and have failed to bring in concrete measures to reduce domestic emissions.

Since taking office, the Conservative government has announced three separate emission-cutting regimes.

To keep in line with U.S. action, Mr. Kent is pursuing a regulatory approach that would impose sector-by-sector rules.

The government is in the final stages of setting rules for the coal-fired power sector, but has yet to say how it will regulate other industries, including the oil sands, the fastest growing source of emissions.

To date, the actions taken by the federal and provincial governments would yield a quarter of the 17-per-cent reductions from 2005 levels by 2020 that Canada has promised to achieve.

Story continues below advertisement

Green Party Leader Elizabeth May – a lifelong environmentalist who had also just returned from Durban – fought back tears as she reacted to the news. She said she had told Canadian ministers that Canada likely could have negotiated less onerous targets in a second round, avoiding the need to spend billions on carbon credits.

"This is not just big, this is disastrous for Canada," she said. "I'm embarrassed to be represented by this government."