* U.S. position hampered by slow progress of Senate bill
* White House to decide on Obama trip in coming days
* World carbon dioxide levels rising rapidly (Adds quotes, writes through with context, details)
By Jeff Mason
WASHINGTON, Nov 23 The United States will propose an emissions reduction target at U.N. climate change talks in Copenhagen in December with an eye toward winning support from U.S. lawmakers who must agree to put it into law.
A senior Obama administration official told reporters on Monday that Washington would make clear in the "next several days" what it planned to put on the table at the talks, and a greenhouse gas emissions goal -- in line with proposals in the U.S. Congress -- would be included.
The White House would also decide in the coming days when and whether President Barack Obama would attend the Dec. 7-18 meeting, the official said.
The talks are meant to help forge a deal to fight global warming after the Kyoto Protocol -- a pact that binds countries around the world to cut emissions -- expires in 2012.
The United States, the world's biggest per capita emitter of greenhouse gases, is a critical player in the talks, but the Obama administration's position has been hampered by slow progress on a climate bill in the U.S. Senate.
Big emitters such as China, the world's top carbon polluter, are watching Washington for its position.
Most nations have given up hopes of agreeing to a binding legal treaty text in Copenhagen, partly because of uncertainty about what the United States will be able to offer.
The senior official said U.S. negotiators will propose an emissions reduction target that takes into account a pending bill in the Senate and a bill passed in the House of Representatives, even though a final law is not complete.
"We don't want to get out ahead or be at odds with what can be produced through legislation," the official told reporters.
"Whatever number we put on the table will be with reference to what we think can come out of the legislative process."
The official declined to say whether the proposal would involve a range or a single figure.
He also downplayed the role that a U.S. law not being in place has played in the overall process.
"It would be a mistake to conclude that the international community's failure to reach a final treaty in Copenhagen was due to the lack of domestic legislation in the United States."
The U.S. House passed a bill that sets a 17 percent reduction target for emissions by 2020 from 2005 levels. A Senate version is shooting for a 20 percent cut.
Senate support for the figure that U.S. negotiators put forward will also be critical because it will have to ratify a treaty once one is finished.
The United States signed Kyoto but did not ratify it.
GOING TO COPENHAGEN, GETTING A DEAL
Denmark, which will host the meeting, still hopes that leaders can agree to a "politically binding" agreement in December under which developed nations would set goals for cutting emissions by 2020, developing nations would agree to slow the rise of their emissions, and the rich would come up with new aid and clean technology to help the poor cope with climate change.
Activists said it was a good signal that the Obama administration was planning to announce actual targets.
"I think it's good news that they've made a decision to put numbers on the table," said Alden Meyer, director of strategy and policy at the Union of Concerned Scientists. "It helps."
Meanwhile the U.N. World Meteorological Organisation said on Monday concentrations of greenhouse gases, the major cause of global warming, are at their highest levels ever recorded and are still climbing,
The head of the agency, Michel Jarraud, said the trend could be pushing the world toward the most pessimistic assessments of the rise in temperatures in coming decades and said this underlined the need for urgent action.
Denmark wants top leaders to come to Copenhagen to illustrate that urgency.
It said on Sunday that 65 world leaders -- including those from Britain, Germany, France, Australia, Japan, Indonesia and Brazil -- have confirmed that they will attend a summit at the end of the Dec. 7-18 period.
Obama's presence is seen as critical to the legitimacy of any deal that would be agreed.
"The president has always said ... if it looks as though the negotiations have proceeded sufficiently that going to Copenhagen would give a final impetus or push to the process ... that he would be willing to go," the U.S. official said.
Obama goes to neighboring Oslo in early December to pick up the Nobel Peace Prize, but world leaders have been invited to come to Copenhagen at the end of the two-week climate meeting.
Climate is likely to feature in talks between Obama and Indian Prime Minister Manmohan Singh on Tuesday in Washington.
India has announced plans to boost solar power from near zero to 20 gigawatts by 2022, but tied chances of success to international finance and technology.
Separately, Indonesia rejected a World Bank study that ranked the nation as the world's third-largest emitter of greenhouse gases, when taking emissions from deforestation and draining of peatbogs on top of industrial emissions. (Additional reporting by Alister Doyle and Robert Evans; Editing by Eric Beech) ((For more on the road to Copenhagen, see [ID:nLL527527] For an overview of climate change stories, click [nCLIMATE])) ((email@example.com; Reuters Messaging: firstname.lastname@example.org))