The announcement marks the first time China has set specific targets for cutting carbon emissions, seen as a major cause of global warming.
Melissa Chan, Al Jazeera's correspondent in Beijing, said: "From the Chinese point of view, their narrative is that this a major commitment that they've made and it's really up to other countries such as the United States and Europe - the developed nations - to make commitments of equal or greater value.
"From their point of view this is a sacrifice and this is as reponsible as they can be as a developing country."
Environmental groups have long complained that China is one of the world's least efficient users of natural resources.
The announcement came shortly after China's foreign ministry said that Wen Jiabao, the Chinese premier, would travel to Copenhagen next month to attend the UN-backed global summit on climate change.
A spokeswoman said Wen's attendance would be a demonstration of China's willingness to work with the international community to curb emissions and tackle climate change.
Ailun Yang, the head of Greenpeace China's climate and energy campaign, welcomed Beijing's statement on Thursday.
"This is definitely a very postive step made by the Chinese side two weeks before Copenhagen, because China is the biggest CO2 emitter and there is enormous pressure on China to make clear what it is going to bring to Copenhagen," she told Al Jazeera.
"I think that China can definitely achieve this target, and I actually believe that it should do more.
"However, China does have a poor record of meeting its environmental measures and there is a gap between the top level government conditions and the local implementation."
The Copenhagen summit had originally aimed to produce a new global climate change treaty to replace the 1997 Kyoto Protocol.
But in recent weeks it has become clear that the meeting is unlikely to produce a binding agreement.
Instead observers expect that summit will at best produce an outline for an agreement to be considered late next year.
China has said it will seek binding pollution cut targets for developed countries at the Copenhagen meeting, but will reject similar requirements for itself.
"When a nation is in a period of fast-paced industrialisation and urbanisation, energy consumption and total emissions go up rapidly," Yu Qingtai, China's envoy to the summit, said on Wednesday.
Yu also accused developed nations of failing to fulfil pledges under the Kyoto Protocol.
Beijing has said repeatedly that it is unfair that all countries should be required to play a role combating global warming since most of the environmental damage was caused by developed nations.