| CANCUN, Mexico
CANCUN, Mexico Mexico scrambled to break an impasse between rich and poor nations over future cuts in greenhouse gas emissions on Friday as 190-nation climate talks went down to the wire.
"It's beginning to stack up and I am cautiously optimistic. We are in a much better situation than we were in Copenhagen at this stage of the game last year," said Chris Huhne, Britain's energy and climate change secretary.
He said that a new failure in Cancun, after last year's Copenhagen summit failed to reach a binding treaty, would reduce the U.N. climate negotiations to a "zombie process," stumbling along forever with no real hope of progress.
Delegates said there were some advances but no breakthroughs in talks in Mexico's Cancun beach resort.
"There were good discussions. The mood in the conference is very positive," Indian delegate Vijai Sharma told Reuters.
The European Union's climate chief was cautious: "There are still important areas where we do not have enough progress," said Connie Hedegaard. "If we do not get things done here in Cancun, it is very difficult to see how you will get from A to B," to a real deal.
The two-week negotiations, due to end on Friday, may well be extended into Saturday.
"It's in the hands of the Mexican presidency," John Ashe, a senior U.N. official who is chairing key discussions to try to resolve a dispute between developed and developing nations about the future of the U.N.'s existing Kyoto Protocol, told Reuters.
Negotiators have to break the impasse about Kyoto to unlock a modest deal to set up a fund to help developing nations tackle climate change, protect tropical forests and agree on a mechanism to share clean technologies.
Mexico's Foreign Minister Patricia Espinosa is presiding over the two weeks of talks among more than 100 environment ministers, and is leading efforts to broker a deal.
"We have very limited time. The issues are complex. (Talks) have been running virtually without stop for many hours," said Rodrigo Brand, spokesman for the Mexican delegation.
NEW TREATY DEMAND
Japan, Russia and Canada have said they will not extend Kyoto, which obliges almost 40 rich nations to cut their greenhouse gas emissions in a first period until 2012. They are insisting on a new, wider U.N. treaty in coming years with other major emitters including China, the United States and India.
Developing nations say that rich nations, which have emitted most greenhouse gases by burning fossil fuels since the Industrial Revolution, must extend Kyoto before the poor sign up for curbs that would damage their drive to end poverty.
Britain's Prime Minister David Cameron spoke with Japanese Prime Minister Naoto Kan by telephone to discuss the standoff over Kyoto, agreed in the Japanese city of Kyoto in 1997. Delegates from Britain and Brazil are overseeing Kyoto talks.
Huhne said "the Japanese have been more flexible in the negotiation sessions." Delegates said that Venezuela had taken a hard-line stance in overnight talks.
The Copenhagen summit collapsed in acrimony, agreeing only a nonbinding accord to limit a rise in temperatures to below 2 degrees Celsius (3.6 F) above pre-industrial times.
Kyoto currently obliges almost 40 developed nations to cut emissions by an average of 5.2 percent below 1990 levels from 2008 to 2012.
(Writing by Alister Doyle and Gerard Wynn, additional reporting by Krittivas Mukherjee in New Delhi and Yoko Kubota in Tokyo; Editing by Eric Walsh)