Bonn talks end amid growing pessimism

The chances of genuine progress towards an international climate change treaty being made at this year's UN summit in Mexico are receding fast, according to one of the top US negotiators involved in the talks.

Speaking on the last day of week-long talks hosted by the UN climate change secretariat in Bonn, US deputy special climate envoy Jonathan Pershing told reporters that he was very concerned that negotiations had once again stalled.

"I came to Bonn hopeful of a deal in Cancun, but at this point I am very concerned as I have seen some countries walking back from progress made in Copenhagen," he said.

He refused to name the countries, but hinted that some developing countries were looking to water down previous pledges to curb the carbon intensity of their economies.

There had been hopes that the latest round of talks would produce a slimmed-down version of the current negotiating text, but instead countries have continued to add amendments to the draft document and as a result it has reportedly swelled from 17 to 34 pages.

The text is meant to provide a framework for a treaty that negotiators will attempt to finalise at the UN's main annual climate change summit in Cancun in November.

But Pershing said the text was currently larger than it needed to be to reach an agreement in Cancun and as a result he was increasingly sceptical that a deal could be brokered this year.

The previous round of UN talks in Bonn in June had delivered some positive results after the fractious end to last year's summit. But observers signalled that the latest round of talks had seen a return to the standoff between rich and poor nations over who should shoulder the bulk of the responsibility for tackling climate change.

Developing countries have repeatedly argued that industrialised countries have failed to table sufficiently ambitious emission-reduction targets and are offering inadequate levels of financing to help poorer nations cope with the effects of climate change.

But in a signal that the US is unwilling to compromise its position, Pershing today accused some developing countries of demanding "staggering sums out of line with reality".

Dessima Williams, a Grenadian diplomat who represents the group of island states, confirmed that poorer nations were likely to push for an increase in the $100bn (£62.8bn) a year of climate-related funding agreed as part of last year's Copenhagen Accord. "It sounds very large," she told reporters. "For the donor countries it is a lot to ask taxpayers to pay. But you must weigh that against the need [of poorer countries affected by climate change]."

The US is already under fire at the talks following the senate's recent failure to pass binding climate change legislation and Pershing's comments are bound to further infuriate poorer countries which feel that the US is not doing enough to move the talks forward.

In more encouraging news, British economist Nicholas Stern told delegates at the Bonn talks that the working group set up to explore ways of raising up to $100bn a year in climate financing was making good progress.

He said the group was looking at a wide range of ideas, including plans to impose carbon taxes, introduce levies on international air fares and set up a new charge for cross-border money transfers.

The group, which includes leading economists, politicians and business tycoons and is co-chaired by the prime ministers of Norway and Ethiopia and the president of Guyana, is due to provide a series of recommendations to the UN in October.

Stern said that world leaders would then be able to discuss the recommendations at the Cancun summit and select the most effective means of raising the finance necessary to help developing countries adapt to climate change and invest in low-carbon infrastructure.

However, he predicted that politicians would need to select a range of different funding options. "No one single source will deliver $100bn by itself, " he said. There is no silver bullet, no hole in one."