Top officials, including Canada's Environment Minister, are lowering expectations that countries will leave a coming round of UN climate talks with a signed deal in hand.
The negotiations in Mexico have been touted as the saving grace of last year's Copenhagen summit. Negotiators in the Danish capital agreed they needed more time to broker a climate deal after deep schisms between countries threw the conference into disarray.
But it now appears the Cancun conference will end much as Copenhagen did, with more than 190 countries putting off a binding climate deal for another day.
Environment Minister Jim Prentice wasn't optimistic Cancun would yield a deal in an interview with The Canadian Press.
"I think everyone, myself included, pointed out after Copenhagen that the process of translating the Copenhagen agreement in principle into a full, binding, international treaty would take several years, and we're well down that road," Mr. Prentice said.
"Cancun is a step in that process, but it's not necessarily the end of the process."
That process seems stalled. Climate ministers and top negotiators from dozens of nations made little headway this weekend in talks at the United Nations. The top UN climate official, Christiana Figueres, said key issues "are frankly in a deadlock," and national interests have hijacked the official negotiating text.
But if talks are now stalled, that's at least progress from last week's candid admission by a top U.S. climate official that the negotiations leading up to Cancun are going backwards.
Todd Stern, U.S. special envoy for climate change, said there has been "backward movement" coming out of Copenhagen. He, too, played down a deal in Cancun.
"Yeah, I do think that that's been going on in the negotiations this year in a number of respects," Mr. Stern said.
Some countries are trying to backtrack on things they agreed to in Copenhagen, he added.
"There have certainly been parties who have been trying to pull back to say - you know, to change the litigation language to say developed countries will take legally binding commitments, developing countries will be purely volunteer, that kind of thing," Mr. Stern said.
"And you know, of course, we're not going to do that."
The UN talks are meant to produce a blueprint to a new climate deal to replace or complement the Kyoto Protocol, the current global agreement, which expires in 2012.
Dozens of countries, including Canada but not the United States, ratified Kyoto. The United States has resisted any replacement deal that doesn't also force big polluters such as China and India to lower their greenhouse-gas emissions.
At the last summit in Denmark, Prime Minister Stephen Harper and other world leaders cobbled together a non-binding "Copenhagen Accord," hours after talks were supposed to have wrapped up.
Some 85 nations have since volunteered to take actions to curb their emissions. Countries also agreed in Copenhagen to set up a multibillion-dollar fund to help developing nations deal with climate change.
At home, the Obama administration has struggled to get a climate bill through Congress.
The House of Representatives passed a bill that would have set up a cap-and-trade system to regulate greenhouse-gas emissions. But efforts to push a much weaker bill through the Senate collapsed over the summer. Hopes for another climate bill appear slim with polls pointing to Republican gains in November's mid-term elections.
American delays also hold up climate legislation in Canada. The Conservative government has largely hitched its environmental policies to whatever comes out of the United States. Both countries have pledged to lower emissions 17 per cent below 2005 levels by 2020.
The Tories say moving forward with climate legislation before the Americans do could put Canadian companies at a disadvantage by placing burdens on them that aren't on their U.S. competitors.
But environmentalists and opposition politicians say that's just an excuse the Harper government uses to delay its own climate-change legislation.
"The U.S. is a huge player, and so they need to be doing a lot more. There's no doubt about that," said Clare Demerse of the Pembina Institute. "But I don't think that that means we can't get anything done."
A recent report from Organization for Economic Co-operation and Development urged the Harper government to press ahead with its own domestic policies.
"The federal government's intention to link its climate policy with the possible cap-and-trade system in the United States is understandable and sensible," the OECD report says.
"However, acting unilaterally would result in domestic and international credibility gains. Canada should thus remain vigilant and not import avoidable climate-policy uncertainty from its neighbour."
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