"In the UK, we want to see urgent steps forward on an international framework," Pearson told a news conference.

"We hope Nairobi will make progress along the road to agreement. We think we need to reach an agreement as soon as possible. 2008-2009 looks a sensible timeframe," he said.

China, the world's second-largest emitter of greenhouse gases after the United States, ratified Kyoto, but as a developing country is exempt from caps on emissions of the heat-trapping gases blamed for stoking global warming.

But Pearson said China would be left behind if its manufacturing sector did not begin to respond to consumers abroad, who he said were increasingly making green choices in their lifestyles and in the products they were buying.

"As a manufacturing world superpower, it is in China's interest to respond to these trends and to support the development of a post-2012 framework," he said.

In China for the first Carbon Expo Asia, Pearson also approved two projects under an arrangement that allows companies from non-Kyoto countries to participate in Britain's carbon market through the Clean Development Mechanism (CDM), which is part of the Kyoto pact.

One of the projects, the Datang Jilin Shuangliao wind farm, will reduce emissions by an average of 92,400 tonnes of carbon equivalent annually.

The second project, the Changling wind power project, will lead to a reduction in emissions of more than 17,500 tonnes of carbon equivalent annually between 2006 and 2012.

Both projects are in China's northeastern province of Jilin.

Under the CDM, credits for carbon emission reductions in developing nations can be sold on specialised exchanges in richer nations or directly to firms that overshoot domestic emissions targets.

Pearson touted CDM as a major source of investment for developing countries to help reduce greenhouse gases and said Britain was poised to take the lead in carbon trading.