Environment Minister Peter Kent refused to confirm or deny reports Canada is walking away from the 1997 agreement that bound 37 industrial countries to limit carbon emissions over a five-year period.
With those commitments expiring next year, the Durban talks centre on finding a new international agreement on combating climate change.
Many environmental groups, developing countries and the European Union want the negotiations to lead to a new version of Kyoto.
Canada, Japan and Russia aren't on board, angling instead for a new deal to bring all emitting countries under the same set of rules, including emerging economies such as China, India and Brazil.
"Kyoto is in the past," Kent said Monday.
But if the Conservative government didn't formally pull out of the agreement now, Canada would be haunted by that past.
After the expiration of the five-year targets, all countries that are party to the protocol will be assessed for how well they fared in a pledge to reduce emissions by six per cent below 1990 levels.
"There would be a public finding, an official finding to the effect that Canada has not met its international commitment," said Jutta Brunnee, a law professor at the University of Toronto.
"And that I think is what the government is wanting to avoid."
After being elected in 2006, the Harper government stated it had no intention of complying with Kyoto, arguing it was too ambitious and not applied fairly.
Canada has since set its own target of cutting emissions by 17 per cent by 2020 over 2005 levels.
CTV reported that Canada had set Dec. 23 as the date it will announce it's pulling out of Kyoto for good.
The withdrawal would also be a finale to a frenzied fall session for the Conservatives, who've sought to fast-track a number of bills, including controversial measures such as the end of the wheat board and several crime bills, in order to have a clean slate in the new year.
Canada would be considered officially out of the treaty a year later, mere days before the five-year deadline for compliance in December 2012.
"Basically it would get them off of the hook with minimal consequence given that they failed to meet targets during the first commitment period," said Hannah McKinnon of Climate Action Network Canada.
"The Canadian government is looking for every escape possible to avoid the consequences of inaction in the face of dangerous climate change and to ensure they can expand the tar sands as projected," she added.
Canada's withdrawal would likely have little effect on the Durban negotiations, said Alden Meyer of the Washington-based Union of Concerned Scientists.
But Meyer said a withdrawal would allow Canada to continue to be a negotiator on the future of the protocol "watering down the treaty and wrecking the job of the rest of us."
Doubts about the Kyoto deal were one reason the EU was conditioning its acceptance of new commitments on an agreement in Durban from China, India and other major emitting countries that they will adopt legally binding commitments by 2015.
Brunnee said Canada should have pulled out of Kyoto sooner.
"The reason they haven't so far, it was politically sensitive and it would have been not a popular move to get out of Kyoto," she said.
"Now I think that's easier because it looks as if there's not going to be an immediate Kyoto successor and everyone is looking for a slightly different approach. It's politically much easier to get out."
Kent was pressed by reporters several times earlier Monday as to whether the government was in fact staying in Kyoto. He refused to answer. He was also asked why he couldn't answer.
"This isn't the day. This is not the time to make an announcement," he told a news conference called to extend funding to the government's clean-air regulatory agenda.
The government had set aside $252 million over two years in the 2011 budget for the agenda and announced Monday it's adding more money and time to bring the commitment to $600.8 million over five years.
Refusing to say whether or not Canada will remain in Kyoto means Canada is in South Africa in bad faith, the opposition charged.
"The presence of the environment minister in Durban is a total charade," said NDP MP Peter Julian.
"He is going to go there, he is going to filibuster, he is going to act like an environmental vandal."
Liberal Leader Bob Rae said whether or not Kyoto was worth extending was beside the point.
"It's that the way we do business with other countries is to be up front and honest and straightforward and I don't find that the government's meeting this standard by saying we're not going to announce anything until the 23rd," he said.
— with files from The Associated Press
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