Gordon Brown’s call for a tax on financial transactions has achieved little support from other world leaders. The UK prime minister advocated a so-called Tobin tax in a speech to G20 finance ministers at the weekend. It was one of four ideas that he floated as a means of ensuring that banks did not have to rely on taxpayers if they needed to be bailed out in future.

Christine Lagarde, the French finance minister, supported the idea of a Tobin tax. But others – including Timothy Geithner, the US Treasury Secretary, and Dominique Strauss-Kahn, managing director of the International Monetary Fund – dismissed the proposal. The IMF, however, is examining one of the other ideas mentioned in Brown’s speech – that banks should be required to pay insurance fees according to how risky they are.

• Gordon Brown's speech to G20 Finance Ministers