US President Barack Obama and British Prime Minister Gordon Brown have laid out their hopes and ambitions for a successful outcome of the London Summit after holding bilateral talks at Downing Street.

Both leaders urged world leaders converging on London for the Summit on 2nd April to find common ground over the key issues of financial regulation, economic growth, strengthening the global financial architecture and helping the world's poorest.

Mr Obama said: 'I am absolutely confident that this meeting will reflect enormous consensus about the need to work in concert to deal with these problems.'

Mr Brown said the 'first duty' of the world leaders gathering in London was to the ordinary people suffering as a result of the global economic crisis and anxious about their jobs, their mortgages and their futures.

'We are within a few hours, I think, of agreeing a global plan for economic recovery and reform and I think the significance of this is that we are looking at every aspect,' he said.

The Prime Minister said the first test for the summit would be to agree to strengthened and more transparent supervision of banks, hedge funds and what is known as the global 'shadow banking system'.

The American President dealt directly with speculation about a split between Anglo-Saxon economies such as the US and UK, and continental European states such as France and Germany, over whether extra economic stimulus measures or tighter financial regulation should be the priority.

'The separation between the various parties has been vastly over-stated,' he said, accusing the media of wanting to 'inject conflict of drama'.
 
'The truth is that there has been extraordinary convergence. I am absolutely confident that this meeting will reflect enormous consensus about the need to work in concert to deal with these problems.'

He said that countries such as France and Germany that had been depicted as 'resistant to' fiscal stimulus measures had instituted very 'significant' fiscal stimuluses.

Mr Obama said how long the crisis would last depended on how effectively countries tackled a series of challenges in the coming months: financial regulation, helping banks deal with toxic assets, managing capital outflows from emerging markets, shielding the poorest countries and reforming international financial institutions.

'All those things will help determine whether this ends up being a slow rolling crisis, that takes a lot more time to cure it, or whether we start seeing significant recovery,' he said. 'I don't think there is any doubt that 2009 is going to be difficult.'

Mr Brown added that 'of course it is difficult and of course it is complex - we have a large number of countries - but I am very confident that people not only want to work together but we can agree a common global plan for recovery and reform.'

Later Angela Merkel, the German Chancellor, and French President Nicolas Sarkozy, held a joint press conference at which they underlined their priorities for reforming the global financial system.

'The most important thing is that we develop a new architecture, a new constitution for financial markets and that we enact very concrete rules and make this very clear in the communiqué,' Mrs Merkel said.

President Sarkozy said he wanted the Summit to deliver 'concrete' results. 'In the results, we want the principle of new regulation to be a major objective...   This is not negotiable,' he said.

He played down rumours that he planned to walk out of the Summit if he did not get what he wanted. 'Angela Merkel and I are on exactly the same page,' he said. 'We think our positions are based on common sense. We both simply wanted to get across that it (the summit) was historic. And when faced with history, you can't sidestep it.'

Meanwhile Egypt's finance minister urged leaders to pay close attention to the needs of developing counties when negotiating a solution to the global economic crisis.

Youssef Boutros-Ghali, who will attend the summit as chair of the International Monetary Fund's policy committee, underlined this assessment by describing the real impact of economic slowdown in developing countries on mortality rates and child nutrition.

Mr Brown will also hold talks at No 10 with Russian President Dmitry Medvedev, Indian Prime Minister Manmohan Singh, Chinese President Hu Jintao and Japanese Prime Minister Taro Aso, who used an interview with the Financial Times to call for more economic stimulus.

Leaders and Finance Ministers from the countries taking part in the Summit have converged on London for official engagements on 1st April ahead of the one-day conference the next day.

After a reception at Buckingham Palace, G20 leaders and their spouses will attend a dinner at 10 Downing Street, where celebrity chef Jamie Oliver has selected a menu based on British foods. Finance Ministers will meet for a dinner at the Tate Modern art gallery in London.