But 1,000 eminent number-crunchers from more than 50 countries have written to G20 finance ministers, urging them to slap a tax on City speculators to help the world's poor.
....They argue that if a tax were levied on transactions such as currency trading at just 0.05%, it could raise hundreds of billions of dollars to be ploughed into international development and climate change projects. Some of the proceeds could also be retained by governments in the countries where the transactions take place, including the UK, helping to repair the hole in governments' coffers.
"The financial crisis has shown us the dangers of unregulated finance, and the link between the financial sector and society has been broken," the letter says. "It is time to fix this link and for the financial sector to give something back to society." It adds that a financial transaction tax is "technically feasible" and "morally right".
The French president, Nicolas Sarkozy, who is chairing the G20, has commissioned Bill Gates to examine innovative ways to fund development, and France and Germany are known to be keen on the idea of a financial transaction tax. Staff from the Gates Foundation have been shuttling between G20 capitals trying to muster support for a tax, which could be imposed by a small group of countries if worldwide agreement proves impossible.