“As more and more heads of State and government confirm their attendance, momentum is building for a successful conclusion to this crucial world gathering,” UN spokesperson Farhan Haq told reporters.

International negotiations on a new agreement to reduce greenhouse gas emissions are set to conclude in the Danish capital, where countries will meet from 7 to 18 December. With only 11 days to go, core political issues – such as financing – remain unresolved, casting doubts on the possibility of achieving a legally binding agreement to combat global warming.

During a visit to Washington D.C. earlier this month, Mr. Ban urged the US to take a leading role in forging a new global pact to combat global warming, warning that the consequences of failure outweigh the cost of tackling climate change.

“No country is more important than the United States in resolving this climate change issue,” he told reporters in the US capital after discussions with congressional leaders.

Just last week the Executive Secretary of the UN Framework Convention on Climate Change (UNFCCC), Yvo de Boer, told a news conference that Mr. Obama’s presence in Copenhagen “would make a huge difference,” adding that he had no doubt that the conference will be successful.

The Secretary-General will use his presence at the Commonwealth Heads of Government Meeting in Port of Spain on Friday to urge leaders attending the gathering to also attend the climate change conference, and to stay committed to reaching an agreement in Copenhagen that is ambitious, equitable, and satisfies the demands of science.

“At Copenhagen, an agreement can and must be reached to set the world on a new course that will ensure a healthy planet, a robust and sustainable economy, and a brighter future for all,” his spokesperson added.

News Tracker: past stories on this issue

UN confident of success at Copenhagen climate summit, with US on board