Asia-Pacific leaders say it will not be possible to reach a climate change deal ahead of the UN conference in Copenhagen.

US president Barack Obama and other world leaders agreed in Singapore today that next month's much-anticipated climate change summit will be merely a way station, not the once hoped-for end point, in the search for a worldwide global warming treaty.

The 192-nation climate conference beginning in three weeks in Copenhagen had originally been intended to produce a new global climate-change treaty. Hopes for that have dimmed lately. But comments by Mr Obama and fellow leaders at a hastily arranged breakfast meeting on the sidelines of a two-day Asia-Pacific summit served to put the final nail in any remaining expectations for the December summit.

"There was an assessment by the leaders that it is unrealistic to expect a full internationally, legally binding agreement could be negotiated between now and Copenhagen which starts in 22 days," said Michael Froman, President Obama's deputy national security adviser for international economic matters.

The prime minister of Denmark, Lars Loekke Rasmussen, the UN-sponsored climate conference's chairman, flew overnight to Singapore to present a proposal to the leaders to instead make the Copenhagen goal a matter of crafting a "politically binding" agreement, in hopes of rescuing some future for the struggling process.

A fully binding legal agreement would be left to a second meeting next year in Mexico City, Mr Froman said.

President Obama backed the approach, cautioning the group not to let the "perfect be the enemy of the good," Froman said. Addressing the Asia-Pacific Economic Cooperation forum later, President Obama talked of the need to limit greenhouse-gas emissions "in Copenhagen and beyond."

Mr Froman said the Danish proposal would call for Copenhagen to produce "operational impact," but he did not explain how that would work or to what it would apply.

A major bill dealing with energy and climate in the US, a domestic priority of President Obama's, is bogged down in the US Senate with scant hope it would be completed by next month, giving the American president little to show in Copenhagen.

The oil and coal industries are powerful lobbies in the US and the Republican party seems to be embracing climate change denial along with its creationist religious dogmas.  The cap and trade bill in the Senate will be even more difficult to pass than the health care reforms currently making their tortuously slow progress through the US congressional legislative process.

I can understand the Republicans wishing to deny Obama a victory on key elements of his programme, but what is it about the Earth as a finite resource they do not understand?  The US frontiers man myth about man discovering ever increasing vistas to conquer and exploit died a death quite a long time ago, but the Republican establishment and their base seem to have entered a Disneyland where more resources can be magicked up from nowhere.

The impotence of the third world - particularly Africa - where the earlier and most devastating effects of climate change are being felt has never been more clearly demonstrated.  Perhaps it is the world economic crises which has changed priorities and made incumbent Governments nervous about anything which appears to increase costs or impact on relative competitiveness in the short term.

However it is far removed from the soaring rhetoric of the early Obama speeches and the "can do" attitude which allowed Kennedy to promise to put a man on the moon within 10 years. Perhaps Obama will make some dramatic proposal on those lines in his Nobel Prize acceptance speech - or in a subsequent appearance in Copenhagen - and then challenge other Governments to follow suit.

It will be quite some time before any Treaty arising from such a proposal can be negotiated, and even longer before it is ratified by sufficient countries to come into force.  That should give Obama ample time to challenge the US Senate to ratify the Treaty - which it must before Obama can sign it on behalf of the US.

What we are seeing now may be the early manoeuvres in the blame game - who is going to be blamed if no agreement is reached?  Right now it will be Obama and the US Senate who will be seen to be holding things up - but another rhetorical flight by Obama containing dramatic proposals could shift the onus of matching his proposals to other countries - and ultimately - to the US Senate.

So why might the Senate ratify a far reaching treaty when it cannot currently progress its own rather limited proposals?  

Firstly, by agreeing to Climate legislation now, the US is forfeiting whatever bargaining leverage it might have with other countries in the final negotiations.  The US contribution will be known in advance - and might even be available if other countries make no concessions and no Treaty is agreed. By making any proposal explicitly contingent on other countries following suit, Obama is not conceding anything at this stage.

However, once a Treaty has been agreed, it will be clear what everyone has put on the table, and it will be possible to calculate the short and long term costs and benefits of the Treaty for all concerned.  A US failure to ratify the Treaty at that point will not only be a PR disaster for the US, but it could result in all the other signatories putting their concessions on ice.  The US Senate will then be directly responsible for the failure to conclude any new Treaty and the gathering storm of climatic consequences around the world.

Ratifying of a Global Treaty agreed by nearly 200 nations is a different proposition to negotiating and agreeing legislation in response to domestic electoral and industry interests alone. Also, by then, the US health reforms will hopefully have completed their tortuous progress through Congress and the Senate will be able to focus on other business.

The problem with this strategy is that as the mid-terms get closer, his bed-wetting moderate wing of the party will get ever more jittery in the face of organised hostile industry led lobbying and advertising campaigns.  Just how high up the Obama priority list is Climate Change?  We may be about to find out.