British finance minister Alistair Darling urged his G20 counterparts on Saturday to work toward a $100 billion deal to tackle climate change but developing nations insisted they did not want to talk about it.

Britain is hosting the third meeting of Group of 20 finance ministers and central bankers this year in St Andrews, Scotland, and is determined to push forward on an ambitious target to meet the costs of climate change by 2020, ahead of a major environmental summit in Copenhagen next month.

"It really is imperative that when we reach the end of the day that we have shown that we have made some real progress," Darling said at the start of talks on Saturday.

"If there isn't an agreement on finance ... then the Copenhagen agreement is going to be much, much more difficult."

But there appeared to be little chance of a breakthrough with many emerging countries questioning whether it should even be a topic of discussion at the forum of leading developed and developing economies, just as they did at a London meeting in September.

"The issue is whether we talk about it or not. Britain is quite motivated on this subject but there are some quite strong objections," a French official said. "The emerging market countries say it should not be discussed for procedural reasons, that the G20 is not the right forum."

BRIC WALL

A European delegation source said the Europeans, notably Britain and EU presidency Sweden, were pushing hard for language on climate change to reach the end of meeting communique, but "are hitting a BRIC wall", referring to the group of four leading developing nations -- Brazil, Russia, India and China.

A 175-nation U.N. meeting in Barcelona ended on Friday with little progress towards a global deal on climate change but narrowed options on helping the poor to adapt to climate change, sharing technology and cutting emissions from deforestation.

The final U.N. preparatory meeting before Copenhangen re-opened a rich-poor divide on sharing the burden of curbs on greenhouse gas emissions and criticism of the United States for not tabling a formal, carbon-cutting offer.

The European source said there was also frustration in St Andrews at the stance of the United States, who were sitting on the fence over climate change financing.

About 40 world leaders plan to go to Copenhagen next month to improve the chances of clinching a climate deal, the United Nations has said.

Darling admitted the chances of getting a figure agreed at this weekend's meeting on the cost of climate change was unlikely but said some advance had to be made to send the right signal.

"There will be quarrelling on climate -- we did not manage to agree on anything. But something has to be included in the communique otherwise there will be a scandal. Britain is very keen," a Russian delegate told Reuters.

German officials predicted no meaningful breakthrough.

"At moment the talks on financing climate protection seem to be at a dead-end," one German delegation source said, picking out China as obstructing progress.

British Prime Minister Gordon Brown, addressing the G20 delegates, said climate change was a test of global cooperation every bit as stern as the world financial crisis.

"It is essential that we urgently move toward resolving the issues that still divide our nations," he said.