Will Obama return to Copenhagen for climate talks?

U.S. President Barack Obama and first lady Michelle Obama greet International Olympic Committee (IOC) members after the presentation of Chicago's bid to host the 2016 Summer Olympic Games in Copenhagen October 2, 2009.

COPENHAGEN (Reuters) - U.S. President Barack Obama came to Denmark to promote Chicago's Olympic bid, but will he come back to push for a treaty to save the world from climate change?

That's the question environmentalists asked on Friday as he made a five-hour stop in Copenhagen where he was rebuffed in his bid to get the International Olympic Committee to pick his adopted hometown of Chicago to host the 2016 summer Games.

The activist group Greenpeace said it had hung a banner with the words "Right city, wrong date" in a public square near where Obama met Danish Prime Minister Lars Lokke Rasmussen shortly after pressing his case for Chicago to the IOC. Rio de Janeiro was chosen for the Olympics.

Environment ministers from about 190 nations will gather in Copenhagen in December to try to seal a U.N. climate pact to take over from the Kyoto Protocol, which runs out in 2012.

But negotiations are stalled over how to spread out emissions curbs, and how much aid industrial nations should give developing countries suffering from the effects of global warming.

Heads of state and government may hold the key to breaking the deadlock, and British Prime Minister Gordon Brown has said he will come to Copenhagen if that would help clinch a deal.

The United States is seen as crucial to the U.N. talks, but Obama's credentials for fighting climate change have come into question as chances dim that the U.S. Senate will pass a bill to reduce greenhouse gas emissions by December.

Obama told Rasmussen he was eager to return to the Danish capital but declined to answer when asked by a reporter whether he would come back for the U.N. negotiations, from December 7 to 18.

"The upcoming meeting here in Copenhagen around climate change is something that we are keenly interested in and I'm looking forward to discussions in depth about how we can move that process forward," he told Rasmussen during a joint appearance before journalists.

Asked on the way back to Washington whether Obama might be willing to attend, White House spokesman Robert Gibbs said no decision had yet been made.

But when pressed, he said, "At this point you've got a meeting that's currently set for not necessarily a head of state meeting ... If it got switched, we would certainly look at coming."

The Danish prime minister wished Obama luck in Chicago's Olympic bid and encouraged him to come again, but did not press him, at least publicly, to show up in December.

World leaders discussed the climate talks at a special U.N. summit in New York last week, but made little concrete progress.

Obama then hosted a G20 meeting in Pittsburgh that yielded an agreement to phase out subsidies on fossil fuels but did little to address the issue of aid for developing countries.

(Editing by Mohammad Zargham)