China has announced that Prime Minister Wen Jiabao will be attending the Copenhagen climate summit from 7 to 18 December.

On Wednesday the United States said President Barack Obama would be at the summit for one day, on 9 December. He will then be on his way to receive his Nobel peace prize in the Norwegian capital Oslo the following day.

China and the United States are two of the world’s largest producers of greenhouse gases. The man charged with coordinating the new United Nations climate treaty, Yvo de Boer, described Mr Obama’s presence as “crucial” if a firm agreement is to be made. The ultimate aim of the conference is to replace the 1997 Kyoto Protocol.

The United States has set a target to reduce its CO2 emissions by 17 percent by 2020 compared with the 2005 level. China’s target is no less than 45 percent, while the European Union is aiming at 20 percent. If a new deal is struck in Copenhagen, the EU has said it is prepared to raise this figure to 30 percent.

Chinese Prime Minister Wen Jiabao - EPA