Glimmer of hope at Copenhagen as US and China take "step forward"

Reports are emerging that late progress towards a compromise deal has been made at the Copenhagen Summit following bilateral talks that lasted nearly an hour between US president Barack Obama and Chinese premier Wen Jiabao.

Citing an unnamed senior US official, Associated Press said the two leaders met for 55 minutes following their speeches this morning. The official said the leaders made a "step forward" on the three main stumbling blocks highlighted in president Obama's speech: emission targets, climate funding and accountability mechanisms.

The reports follow earlier indications that China and India could yet submit to US demands for some form of accountability mechanism to independently verify greenhouse gas emissions.

He Yafei, the Chinese vice foreign minister, was reported as saying that China would improve the transparency of its emissions reporting and "consider international exchange, dialogue and cooperation that is not intrusive, that does not infringe upon China's sovereignty".

There were also reports from the New York Times that the UN was preparing to let the summit continue past its scheduled closure this afternoon and had advised officials to extend their stay until Sunday night.

Meanwhile, the first high-profile walkout appeared to occur when Venezuelan president Hugo Chavez said he would not sign an agreement "cooked up" by rich nations and was leaving.

"We can't wait any longer, we are leaving. We will reject any document that Obama tries to slip under the door," he said, adding that the US offer of $10bn of climate funding for poorer countries was a "joke".

There was also frustration at the draft document prepared overnight by a group of industrialised and emerging economies with a number of poorer countries expressing fears that it was far too weak for them to sign.

The leaked draft document, obtained by the Guardian, said only that temperature rises "ought not exceed 2C", and contained no solid emission targets for rich countries.

Developing nations also expressed fears that the wording of the document would allow the US to use 2005 rather than 1990 as the baseline for its emission cuts and could yet be used to scrap the Kyoto Protocol and allow the World Bank to play a major role in distributing climate funding.