Sixty-five world leaders have said they will attend the Copenhagen climate summit in December, and several more have responded positively to invitations, Danish officials said Sunday.
But the world's top three carbon polluters _ the United States, China and India _ have not indicated whether their leaders will attend the meeting, and that could have a big impact on its chances of reaching a deal.
The nations that plan to send their leaders to Copenhagen include Australia, Brazil, France, Germany, Indonesia, Japan, Spain and the United Kingdom, a Danish official said, speaking on condition of anonymity because he is not an official spokesman.
At a party convention in Odense, Denmark, Danish Prime Minister Lars Lokke Rasmussen said Sunday he was encouraged by the fact that "more than 60" leaders had confirmed their participation.
"This shows that heads of sate and government are ready to fly in, realizing that the political momentum is pointing towards Copenhagen as the place ... to address the outstanding issues so we can conclude an ambitious deal," he said. "To cut through the outstanding issues and make an ambitious deal, then the active involvement of heads of state and government is crucial."
Loekke Rasmussen _ the host and chairman of the climate talks _ last week sent out formal invitations to world leaders in 191 countries to attend the Dec. 7-18 U.N. climate summit in Copenhagen.
The conference had originally been intended to produce a new global climate-change treaty on limiting emissions of greenhouse gases that would replace the 1997 Kyoto Protocol. However, hopes for a legally binding agreement have dimmed lately, with leaders saying the summit is more likely to produce a template for future action to cut emissions blamed for global warming.
President Barack Obama, China's Hu Jintao, and Prime Minister Manmohan Singh of India have not publicly said if they will attend the summit, although U.S. climate delegate Jane Lubchenco has said Obama is "actively considering" that.
However, Obama's advisers say he is working in private to push toward a solution that would yield a binding agreement at a meeting in Mexico next year. Obama raised such issues during a meeting with Rasmussen on the sidelines of the recent Asia-Pacific Economic Cooperation summit in Singapore.
British Prime Minister Gordon Brown, who is among those heading to Copenhagen, said Sunday in a letter to Rasmussen that the meeting needs national leaders "to make the final decisions necessary to achieve agreement."
"I am extremely encouraged that so many heads of state and government have now publicly confirmed their intention to go. This is an important signal and I shall continue to encourage others to do so," Brown wrote.
Britain has pushed other nations hard in recent months to commit to a legally binding treaty at the summit, although Brown has acknowledged that a pact may not be sealed until 2010.
"The Copenhagen agreement must allow for immediate implementation of its provisions, while also including a clear commitment to convert the agreement into an internationally legally binding treaty as soon as possible," he wrote to Rasmussen.
Brown will hold talks with Commonwealth leaders at a summit in Trinidad and Tobago next weekend.
Rasmussen also plans to attend those talks.
Associated Press writers David Stringer in London and Malin Rising in Stockholm contributed to this report.