China's CO2 emissions are increasing faster than previous estimates predicted, according to a group of US economists who fear the country's rapid growth could derail global efforts to stabilise atmospheric greenhouse gas levels.

Researchers at the University of California, Berkeley and UC San Diego said this week that China's CO2 emissions will increase by 11 per cent annually between 2004 and 2010.

Previous estimates used by the UN’s Intergovernmental Panel on Climate Change, said the regional area including China would see an annual increase in CO2 emissions of between 2.5 to five per cent over the same period.

The new research is likely to increase international calls for China to sign up to binding emissions cuts as part of a post Kyoto agreement on climate change.

Speaking at the China Now Sustainability Conference last month, Lord Stern said China would probably have to cut its emissions by half to help stabilise global warming.

The US report found that by 2010 China will have added 600m tons of CO2 to the atmosphere since the millennium. It argued that if China does not curb its emissions growth, the greenhouse gases from China alone would out strip the 116m tons of CO2 reductions that countries participating in the Kyoto Agreement's first commitment phase up to 2012 have pledged to deliver.

The report also warned that attempts by the Chinese government to slow emissions growth where be undermined by the rapid expansion in energy use across the country's interior provinces.

"Wealthier coastal provinces tended to build clean-burning power plants based upon the very best technology available, but many of the poorer interior provinces replicated inefficient 1950s Soviet technology," explained Richard Carson, UC San Diego professor of economics. Once power plants are built then can last for up to 75 years, he added, arguing that provincial officials have " locked themselves into a long-run emissions trajectory".

A full version of the report will be published in the May issue of the Journal of Environmental Economics and Management. The findings were based on pollution data from 30 Chinese provinces and China’s official waste gas emissions data.