Finance ministers from the world's biggest economies are gathering in Sussex to discuss a global response to the recession. The G20 meeting in Horsham comes before the heads of government summit in London next month when Prime Minister Gordon Brown has his sights set on a "global new deal". The Chancellor will be urging his counterparts to sign up to recession-fighting fiscal stimulus measures similar to those adopted by the Treasury. He is calling for reform of the International Monetary Fund and the World Bank, as well as rules to ensure financial institutions build up a "buffer" of cash in good years to allow them to continue lending during a downturn. There are doubts over the likelihood of agreement on a global spending plan after France and Germany spoke out against the co-ordinated fiscal stimulus that Mr Brown and US President Barack Obama see as a vital part of any rescue package. At a joint press conference with French President Nicolas Sarkozy, Ms Merkel said: "The issue is not spending even more but to put in place a regulatory system to prevent the economic catastrophe that the world is experiencing from being repeated." Paris and Berlin are among several European capitals thought to be nervous over US Treasury Secretary Tim Geithner's call for a stimulus in the form of tax cuts worth 2 per cent of GDP to boost demand. Meanwhile, Conservative leader David Cameron admitted the Tories failed to predict the financial crisis coming as early as they could have done, saying: "Of course I'm sorry that we have got some things wrong. "We were right to call time on Government debt but should we have said more about banking debt and corporate debt? Yes, we should have done." The admission will put more pressure on Gordon Brown to apologise for the economic crisis.