Dealmakers called in to break the deadlock over US and China’s war on currency

American and Chinese officials bickered until 3am over President Obama's accusation that the far eastern giant was destroying jobs in the West by holding down its currency to create an exports boom.

A compromise was only struck after British, French and Russian officials were called in as peacemakers. The summit said that global leaders will develop "indicative guidelines" to tackle serious trade imbalances and had agreed to unite against competitive devaluations.

However, the deal fell far short of the strict restrictions proposed by Mr Obama, who left saying the summit had struck "singles" rather than a "home run". The tense talks contrasted with the jubilation and unity shown at the London G20 nearly two years ago.

David Cameron said progress was being made, citing his own private talks with the Chinese leadership when he urged them to open their markets to western goods. "Slowly, slowly China is moving into a position of actually increasing domestic consumption, rebalancing its economy," Mr Cameron said.

But Chinese officials scoffed at President Obama's call for a four per cent limit on national trade deficits and surpluses. "Don't make other people take the medicine for your disease," a commerce ministry official said.

Beijing said the US was just as big a culprit, arguing that a further $600 billion (£370 billion) of quantitative easing had deliberately weakened the dollar to make imports more dear.

Germany, which is the second biggest exporter, also opposed the US proposals. But there were fears that the disagreement could threaten growth. An annoyed President Obama said imbalances "helped to contribute to the crisis that we just went through".

He went on: "This is something that I raised with President Hu of China and we will closely watch the appreciation of China's currency." European leaders said they were "satisfied" with the outcome.

The summit also committed itself to completing the Doha trade talks, saying that 2011 was a "critical window of opportunity, albeit narrow" to make a breakthrough.

At the same time, Britain, France, Germany, Italy and Spain issued a joint declaration to try to calm bond market jitters over a possible future EU bail-out fund for Ireland which has a severe debt crisis.