The current Kyoto Protocol binds only the emissions of industrialized countries from 2008-2012. Poor and emerging economies want to extend the pact, creating a deadlock at U.N. climate talks running from June 6 to 17 in Bonn, Germany.
The confirmation makes it clear Canada is following the line its ruling party pursued ahead of last month's election.
"Now that we've finished our election we can say now that Canada will not be taking a target under a second commitment period of the Kyoto Protocol," Judith Gelbman, a member of Canada's delegation, told a negotiating session of the talks.
Canada has also previously said it could not achieve the binding emissions cuts it has committed to under the first round of Kyoto up to 2012, infuriating environmentalists and developing countries.
The U.N.'s top climate official, Christiana Figueres, said on Monday that the talks would now miss a deadline to launch a binding successor to Kyoto at the end of next year, because even if countries agreed a deal, they subsequently would have to be approve it in national parliaments in a lengthy ratification process.
The talks in Bonn were all but deadlocked on Wednesday on what items to include in the agenda of the meeting, and also over the long-running spat over whether or not to extend Kyoto.
Global carbon emissions last year rose at their fastest rate in more than four decades, up nearly 6 percent at about double the annual rate of increase over the past decade, data released by oil company BP showed.
(Reporting by Gerard Wynn; Editing by Jonathan Lynn)
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