British Prime Minister Gordon Brown told finance ministers from the Group of 20 rich and developing countries it was time to consider a global financial levy such as a tax on transactions or an insurance fee.
In its last meeting as chair of the Group of 20 before South Korea takes over next year, Britain is attempting to push through discussion of issues it views as critical to future world economic growth.
Reflecting its last-chance position, Prime Minister Gordon Brown superseded his Treasury chief Alistair Darling to address officials directly, saying it was time "to discuss whether we need a better economic and social contract to reflect the global responsibilities of financial institutions to society."
But he said Britain would not act alone, and that any measures must be implemented by all major financial centers and should reinforce existing measures to enhance the stability of the international financial system.
Brown's comments bolster earlier calls from former German Finance Minister Peer Steinbruck for a global tax on all cross-border financial transactions.
Critics argue that measures such as the so-called Tobin tax _ a flat tax on currency transactions named after the Nobel Prize laureate James Tobin _ would just dry up world financial flows.
Supporters suggest the money could be used to protect countries from spillovers of financial crises.
The money could also be used to assist poorer countries in the battle against climate change _ another issue being pushed by Britain at the gathering in the university and golfing town of St. Andrews in northeast Scotland.
Darling urged the officials to reach an agreement on bearing the cost of fighting climate change before a UN summit on global warming next month.
Darling said officials need to agree on a finance package to help poorer nations develop green industries and adapt to climate change.
"I think that it really is imperative that when we reach the end of the day, that we have shown that we have made some real progress in dealing with what is a very real and urgent problem now," Darling said. "We will do everything that we can to reach that agreement in advance of the Copenhagen meeting."
There have been disagreements about which forum was the most appropriate place to discuss funding to fight climate change.
The push to put it on the agenda here reflects concern that nations will fail to agree in Copenhagen on Dec. 6 on a successor to the Kyoto treaty limiting carbon emissions.
"It really is important ... that we as finance ministers are engaged in this, because if there isn't an agreement on finance ... then the Copenhagen agreement is going to be much much more difficult," he said. The G-20 represents around 90 percent of the world's wealth, 80 percent of world trade, and two-thirds of the world's population.
The EU has said that there should be a euro100 billion annual package of public and private finance by 2020 and has urged the U.S. to lay out its position.
But the Obama administration has been preoccupied with prickly domestic issues such as healthcare.
Danish Prime Minister Lars Loekke Rasmussen said it was now "obvious" that the December climate change talks "can't achieve the final result in terms of the new legally binding treaty which goes into all details."
But he said finance ministers held the key to a final deal, urging them to come up with concrete proposals on funding to help developing nations tackle and cope with a warming climate.
In a speech to the G-20 meeting, he called on officials to set up a global climate fund that "should be ready to work immediately." He also asked them to keep an open mind on raising funds from new areas such as a global cap-and-trade program for air and sea travel.
The climate issue has been the focus of protests around St. Andrews. A small group of protesters blocked the coastal road Friday night between the town and the nearby resort where the meeting was held by chaining themselves together. On Saturday around 200 demonstrators gathered at West Sands beach on Saturday with a group dressed as bankers sticking their heads in the sand.
There are also divisions among officials over attempts to secure future global growth.
Host country Britain, still mired in recession, is keen to continued international effort to support a still fledging recovery, while other G-20 nations, including the United States, Japan and Germany, want to debate ending measures to boost growth.
The finance ministers and central bankers are trying to find a way to make good on a pledge by world leaders at their September summit in Pittsburgh to subject their economic policies to the scrutiny of a peer review. That process would determine whether each country's efforts were "collectively consistent" with sustainable global growth.
The goal is to avoid repeating problems like huge trade deficits and credit-fueled consumption in the U.S., and massive trade surpluses and savings in China and elsewhere. China's appetite to fund U.S. debt by buying Treasuries was seen as playing a major role in fueling the U.S. housing boom and subsequent collapse.
The G-20 is comprised of Argentina, Australia, Brazil, Britain, Canada, France, Germany, India, Indonesia, Italy, Japan, Mexico, Russia, Saudi Arabia, South Africa, South Korea, Turkey, the United States and the rotating EU presidency.
