System on way to cap carbon output

China will gradually set up a mechanism for limiting its overall carbon emissions and accelerate development of a national carbon market, according to the country's chief climate change negotiator.

The country cut carbon dioxide emissions per unit of GDP by 28.56 percent last year compared with 2005, said Xie Zhenhua, vice-minister of the National Development and Reform Commission.

This is equivalent to a reduction of 2.5 billion metric tons of carbon dioxide emissions, thanks to the nation's efforts in promoting energy efficiency and optimizing the energy mix, Xie said on Saturday at the two-day China Low-Carbon Development Strategy Conference in Beijing.