Secretary-General Ban said the September forum on global warming will be one of the most important initiatives in the history of the United Nations, and he intends to use the forum to consolidate and generate firm interntional political will.

In the past, President George W. Bush has been the major holdout, rejecting Kyoto’s mandated curbs in greenhouse-gas emissions because the treaty makes no demand on fast-growing nations such as China and India.

U.S. participation will be key to any new framework on climate change, and Ban has told Japan’s Asahi Shimbun that, due to growing perception and awareness among the international community on global warming, the U.S. has been changing its tune and is expected to be more cooperative.

The U.S. is “going to have another meeting immediately following my meeting here, but I am sure that the U.S. initiatives and meetings will be part of this UN negotiating forum,” Ban said.