Barack Obama acknowledged today that time has run out to secure a binding climate deal at Copenhagen and began moving towards a two-stage process that would delay a legal pact until next year at the earliest.

During a hastily convened breakfast meeting in Singapore, the US president supported a Danish plan to salvage something from the moribund negotiations by aiming for a broad political agreement and postponing contentious decisions on emissions targets, financing and technology transfer.

While this falls short of hopes that Copenhagen would lock in place a new action plan for the world, it recognises the lack of progress in recent preparatory talks and the hold-ups of climate legislation in the US Senate. "There was a realistic assessment … by the leaders that it was unrealistic to expect a full internationally legally binding agreement to be negotiated between now and when Copenhagen starts in 22 days," said Michael Froman, deputy national security adviser for economic affairs.

Danish Prime Minister Lars Lokke Rasmussen, the host and chairman of the climate talks, flew overnight to Singapore to pitch the deferral plan to 19 leaders, including Obama and Chinese president Hu Jintao, at an unscheduled event during the Asia-Pacific Economic Cooperation summit. He insisted that the Copenhagen talks could still set political targets and outline commitments.

"Given the time factor and the situation of individual countries we must, in the coming weeks, focus on what is possible and not let ourselves be distracted by what is not possible," he said. "The Copenhagen agreement should finally mandate continued legal negotiations and set a deadline for their conclusion."

Obama was said to have spoken in support of the proposal, cautioning the group not to let the "perfect be the enemy of the good", Froman said.

The proposal by Denmark, the host and chair of the climate talks, would set the stage for a political accord at Copenhagen next month and the setting of a new deadline for countries to agree on targets, levels of funding and verification of commitments.

This would give breathing space for the US Senate to pass carbon-capping legislation, allowing the Obama administration to bring a 2020 target and financing pledges to the table at a UN climate meeting in Mexico or Germany in mid-2010.

It was unclear if China, the world's biggest emitter, supported the delay, but other leaders said there was little choice.

"Leaders … were clear in their view that the current officials-led process is running into all sorts of difficulties, and therefore it is time for leaders, politically, to step in," the Australian prime minister, Kevin Rudd, told reporters after the meeting with Rasmussen. "It's going to be tough as all hell, but let me tell you I believe everyone is seeking, right now, to put their best foot forward, and that was reflected in what transpired around a small table of 20 world leaders this morning."

The extension of the process is not unexpected, given the flurry of downbeat statements by world leaders in recent weeks. It may avoid a total breakdown at Copenhagen, but the delay has frustrated those who feel time is running out to prevent calamitous levels of climate change.

"Heads of states must go beyond simply discussing the problems. They have to start solving them," said Diane McFadzien of the Worldwide Fund for Nature. She noted that the APEC leaders deleted emission reduction targets in their final declaration.

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