China, the world's biggest polluter, unveiled plans today for a national carbon market likely to become the world's largest exchange for emissions credits. <br/><br/>Zhang Yong, vice chairman of China's National Development and Reform Commission said, the purpose of this programme is to reduce greenhouse gas emissions.<br/>'<br/>Environmentalists praised the move as an important step in the battle against climate change as China burns more coal<br/>than any other country, giving it the ignominious title of top greenhouse gas emitter.<br/>'<br/>Although the long-delayed emissions exchange scheme will initially cover just the power generation sector, it is expected to surpass the European Union's carbon market, currently the world's biggest.<br/>'<br/>China is seen as a potential leader in the fight against climate change after the US retreated from the Paris accord.