President Obama's confirmation that he would attend the Copenhagen summit came after the United States indicated it would set targets for reducing greenhouse gas emissions at the UN summit which runs from December 7-18.

Administration officials in Washington said Obama will offer to cut greenhouse gas emissions by 17 percent from 2005 levels by 2020. He would also offer a 30 percent reduction by 2025 and a 42 percent drop by 2030, AFP news agency reported.

The presence of President Obama had been seen as crucial to unlocking stalled negotiations between industrialized and developing nations.

Obama is scheduled to be in Copenhagen on December 9, a day before he is due to receive the Nobel Peace Prize in Oslo, Norway. Administration officials in Washington would not say whether Obama is going to return to Copenhagen at the end of the conference, when other leaders will be gathering to finalize an agreement.

Merkel has said she's going

Around 65 world leaders, including German Chancellor Angela Merkel, have already said they would be attending the UN climate talks, which are expected to work towards a new global treaty to replace the Kyoto Protocol, which expires in 2012.

The Kyoto Protocol is an international agreement linked to the United Nations Framework Convention on Climate Change. It sets binding targets for 37 industrialized countries and the European Union for reducing greenhouse gas emissions. One of the challenges of a new agreement will be to find a way of including emerging economies, such as China and India.

On Tuesday, following bilateral talks with Indian Prime Minister Manmohan Singh at the White House, Obama said that countries must "reach a strong operational agreement that will confront the threat of climate change while serving as a stepping-stone to a legally binding treaty."

Chinese Premier Wen Jiabao will also attend the summit, Foreign Ministry spokesman Qin Gang said Thursday.

Along with the US, China is the world's biggest polluter. Beijing has gone on record saying that it will not sacrifice growth to cut greenhouse gas emissions.

nrt/dpa/AP

Editor: Michael Lawton