US President Barack Obama downplayed differences between world leaders over strategies to boost world economies at the G20 summit in London. “I think that the separation between the various parties involved has been vastly overstated," he said on Wednesday.

As world leaders gathered in London on Wednesday for a much-awaited summit of the richest countries in the world, Obama met UK Prime Minister Gordon Brown and Russian leader Dmitry Medvedev ahead of talks with China’s President Hu Jintao for the first time.

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In a speech after the meeting, Barack Obama insisted that the G20 should concentrate on ‘common ground’ and not occasional differences. On Tuesday, France warned it could walk out of the summit if it does not secure agreement on regulatory reform.

But Brown said on Wednesday he was confident that French President Nicolas Sarkozy would stay at the summit, which officially starts on Thursday.

Reporting from London, FRANCE 24’s international editor Rob Parsons said it would be “an enormous blow to the international financial system” if Sarkozy did desert the summit, adding however that it was an “extremely unlikely” incident.

Obama also met his Russian counterpart Dmitry Medvedev. The two leaders agreed to pursue talks on potentially far-reaching reductions of their nuclear arsenals. Obama said he planned to visit Russia in July.

Testing times for Obama

The G20 summit is Obama’s first major international gathering after two months in the Oval Office. As president of the country which ushered in the present economic crisis, he is under intense pressure to produce solutions.

However, differences already emerged which might prevent leaders from reaching a consensus at the summit.

While the US and others favour stimulus to boost economic growth, European leaders, led by France and Germany, are sceptical about spending more money and insist on tighter financial regulation to rein in market excess.

In a newspaper interview on Wednesday, Japanese PM Taro Aso underlined his country’s experience in tackling financial crises, dismissing Germany's warnings about the dangers of excessive spending.

High security in London

London is under tight security as authorities expect several demonstrations to converge on the Bank of England.

Workers in London’s financial district were urged to stay at home or to dress down to avoid attracting the attention of protestors. According to the UK daily The Guardian, the police operation to secure the G20 will cost an estimated 7.2 million pounds and involve 3,000 extra officers.