Prime Minister Stephen Harper arrives at a wrap-up press conference at the end of the UN climate change conference in Copenhagen on Friday. (Sean Kilpatrick/Canadian Press)

Prime Minister Stephen Harper and other world leaders — including those from the U.S., China, India, Brazil and South Africa — are leaving Copenhagen with a compromise climate deal and a vow to work out the details.

The agreement offers money to developing nations to help them fight global warming provided they agree to open their books to international scrutiny.

Harper called it a "comprehensive and realistic" agreement, while U.S. President Barack Obama hailed it as a "meaningful and unprecedented breakthrough."

However, the agreement is not binding and does not set new greenhouse-gas reduction targets. Instead, countries are to set their own emission-reduction commitments, which would not be legally binding.

U.S. President Barack Obama makes a statement at the climate change conference on Friday. (Susan Walsh/Associated Press)

Those commitments will be the subject of further negotiation, with the aim of a final deal at next year's summit in Mexico. It's a compromise following 12 days of divisive talks that saw hopes dwindle as the summit's close drew near.

Talks in the Danish capital have been marked by rifts between rich countries and developing nations, and between the world's two biggest polluters — the U.S. and China.

Obama met privately with Chinese Premier Wen Jiabao twice on Friday morning and afternoon to try to come up with an accord, amid deep divisions between rich and poor nations. Neither leader has publicly offered any new commitments to cut the greenhouse gas emissions that cause global warming as they addressed the conference.

Obama said earlier Friday that world leaders' ability to take action on the issue "hangs in the balance."

"I believe we can act boldly and decisively in the face of a common threat," Obama told the conference earlier Friday. "That's why I come here today not to talk, but to act."

Obama called for transparency in determining if countries are meeting their commitment, a remark squarely aimed at China, which is reluctant to allow international scrutiny of its carbon emissions.

A deal without the sharing of information would be a "hollow victory," Obama said.

The U.S. president also displayed some impatience with the pace of negotiations.

"No country will get everything that it wants," he said.

Other political leaders gathered in Copenhagen have been expressing doubt about the conference.

"A deal is still possible, but as of this morning, I think we have a climate change summit in crisis," said Achim Steiner, the head of the UN Environment Program, adding that what the conference needs now is some "inspiring leadership."

Abandoning hopes of reaching a comprehensive deal, a group of about 25 countries sought their own agreement on a two-page political statement setting out critical elements, key among them the mobilization of $30 billion US in the next three years to help poor countries cope with climate change.

As negotiations evolved, several new drafts of the document, titled the Copenhagen Accord, emerged, each time with key clauses updated and modified. Later drafts said rich countries should cut their greenhouse emissions by at least 80 per cent by 2050.

Obama arrived in Copenhagen early Friday, and held an unscheduled meeting with almost 20 world leaders, including the heads of Britain, France, China, Russia, Brazil and a dozen other countries. Harper later met with Obama as the U.S. leader had lunch with about a dozen leaders.

Following that meeting, French President Nicholas Sarkozy accused China of slowing the negotiations. Sarkozy said China is still not agreeing to allow international monitoring.

While Western leaders have pointed at China, some critics have accused the United States of coming into the negotiations too late, with no new proposals.

Jiabao said developed countries must bear their share of responsibility.

"In addressing climate change, it is inadmissible to turn a blind eye to historical responsibilities, per capita emissions, and different levels of development, [which] would undermine the efforts of developing countries to get rid of poverty and backwardness," he said.

Economic rift

Lars Lokke Rasmussen, the Danish prime minister, said earlier that talks went well Thursday night, and that compromise and consensus were starting to emerge.

However, the rift between rich and poor nations appears to be as wide as ever. A draft agreement from the U.S., Britain and other countries circulated overnight, but was rejected.

Some negotiators from developing countries have called the situation disappointing and confusing.

Harper arrived on Thursday and participated in Friday's sessions. In a brief statement on Thursday, Environment Minister Jim Prentice repeated the government's position that it wants what he calls a "fair deal" for all parties.

With files from The Associated Press