'I think the broad consensus of private economists and businesses are that we're beginning to see growth in the United States, and around the world we see exports rising and forecasts for growth are being revised upwards.

'This is encouraging,' he said, 'but we have a ways to go.'

He said the leaders are 'going to keep working to sustain the progress we've seen. And I can say with confidence, based on my discussions with finance ministers and central bank governors from around the world, there is a common, shared commitment to make sure we're working together to sustain these early signs of recovery and growth.'

One of the key goals is preventing such a crisis from occurring in the future, he said.

The economic summit marks the third time in a year that the world's top industrial powers have gathered. They met in November in Washington and followed up with an April session in London.