The top US envoy for climate conference in Copenhagen rejected the argument Wednesday that the US owes the world "reparations" for carbon emissions over the past decades.

A balloon with "This is the size of one tonne CO2" written on it is seen in Copenhagen, capital of Denmark, Dec. 9, 2009, on the occasion of the United Nations Climate Change Conference. [Lin Miao/Xinhua]

US special envoy Todd Stern said in a press release that the US recognizes its historic role in global warming, but he rejected any notion of guilt or reparation.

The US is not in debt to developing countries because the greenhouse effect is a "relatively recent phenomenon," Stern said.

The US urged major developing countries to offer carbon emission reduction plans in negotiations and pressured them to take on more responsibilities.

He said the US was planning to join other developed nations in giving aid to developing countries to deal with climate change, but he dismissed the proposal that developed nations provide financial aid and clean energy technologies to major emerging economies like China and India.

China expects the US and the EU to bring more notable targets for cutting their carbon emissions, said Xie Zhenhua, the Chinese chief negotiator said at the climate talks Tuesday.