World leaders have snubbed the next round of international climate change negotiations in Mexico next month amid fears the talks will collapse.
The last United Nations summit on global warming in Copenhagen, at the end of last year, ended in failure and recrimination. More than 100 heads of state turned up hoping to be part of a deal that would "save the world", but failed to get any legal agreement to stop rising temperatures.
This year, they are declining even to attend, instead sending environment ministers and playing down the talks as much as possible.
The process is dogged by a disagreement over the best way to limit the growth in greenhouse gases, which are blamed by scientists for rising temperatures. Environmentalists believe the best approach is a binding treaty that will force all countries to cut carbon emissions. But at the last major meeting before the Cancun summit, held in China last week, delegates were still in dispute.
Barack Obama, US president, has failed to bring in any broad legislation to limit greenhouse gases, while the Chinese are uncomfortable about having their own emissions measured. The talks in China ended in mistrust, with both sides accusing the other of failing to make clear promises to cut carbon.
Jonathan Pershing, the US chief negotiator, admitted: "There is less agreement than one might have hoped at this stage,"
Britain has robust targets to cut its own greenhouse gases by 80 per cent by 2050 and is keen to achieve a global deal. But European Union negotiators have limited say amid clashes between the US and China.
Chris Huhne, the UK's climate change secretary, will be in Cancun to urge different nations to work together. Behind the scenes British negotiators say the best hope for the 170 countries meeting in Cancun, from Nov 29 Dec 12, is a deal on climate finance and rainforests.
Kelly Dent, Oxfam's senior climate change adviser, is hopeful that rich countries will help poor nations to adapt to climate change and protect rainforests. "The outlines of an agreement for Cancun are beginning to appear, but there is still so much more [that] governments urgently need to fill in to make it real," she said.
There are fears that Cancun may not even meet the drastically low expectations of its participants, and that the UN-wide process of negotiation could be abandoned in favour of thrashing out an agreement in a smaller group such as the G8.
The eventual goal is to cut greenhouse gases in half by 2050 in order to keep the rise in global temperatures below 2C (3.6F).