WASHINGTON U.S. President Barack Obama is unlikely to sign climate legislation ahead of a U.N. global warming meeting in Copenhagen that starts in early December, the White House's top climate and energy coordinator said on Friday.
"We'd like to be (finished with) the process. That's not going to happen," Carol Browner said at a conference called the First Draft of History. She said the administration is committed to passing comprehensive energy and climate legislation "on the most aggressive timeline possible."
Democratic Senators John Kerry and Barbara Boxer unveiled a climate bill this week but it remained unclear whether it would win the required 60 Senate votes for passage.
Even if the bill does pass, the Senate and the U.S. House of Representatives would have to reconcile their versions of the bill in committee.
That would leave little time for Obama, who has made climate one of his top issues, to sign the bill before 190 nations are due to meet in Copenhagen from early December in hopes of hammering out a successor agreement to the Kyoto Protocol on global warming.
The U.S. Congress has been focused on health care legislation, delaying work on the Kerry-Boxer bill.
White House spokesman Robert Gibbs told reporters later on Friday that Obama would consider attending the climate talks in the Danish capital if heads of state were invited.
Browner said she did not know if a global agreement on binding cuts in greenhouse gas emissions could be made in Copenhagen. But she had hope for progress saying the world's top leaders recognize global warming is a problem.
"Copenhagen isn't the end of a process, it is the beginning of a process," she said.
The administration has been pleased with recent talks with China, the world's top greenhouse gas polluter, on tackling climate change, she added.
Browner expressed optimism Congress would pass the bill in due time but said the administration has options if that did not happen.
The U.S. Environmental Protection Agency could work with states that already have formed carbon markets to extend those programs, said Browner, former head of that agency.
"That may be a way in which you could form a regime using these models that are already out there," she said.
Ten eastern U.S. states have formed the Regional Greenhouse Gas Initiative to regulate carbon dioxide emissions from power plants. In addition, California and several other states in the West plan to regulate six greenhouse gases from smokestacks and tailpipes beginning in 2012.
(Reporting by Timothy Gardner; Editing by David Gregorio)