China's private consumption accounts for little more than a third of its economy, while it exceeds 70 per cent in the US or Britain.
By contrast, China's households saved about 40 per cent of their disposable incomes last year, while the US savings rate was just more than three per cent.
Obama is hoping to bring the Chinese on board with the plan by pushing for Beijing and other emerging economies to get a greater voice at the International Monetary Fund.
However, China has so far appeared reluctant and there seem to be few concrete proposals about how to achieve the massive rebalancing of global consumption.
Meanwhile, European leaders will be pressing for changes to financial regulations to prevent a repeat of last year's financial collapse.
France is encouraging the other G20 nations and the EU to follow its lead in seeking caps on excessive bonuses paid to bankers, which they say rewarded excessive risk-taking.
On Wednesday, Nicolas Sarkozy, the French president, urged world leaders at the UN to condemn "the behavior of those who still continue to grow indecently rich, after leading the world to the brink of disaster".
Axel Weber, the head of the German central bank, voiced optimism that G20 leaders would agree to changes.
"In Pittsburgh, we have to say, there are still fires to be put out, we'll see later how to do the mopping up"
"I am happy that G20 leaders and regulators have a broad consensus on the issues and on the agenda," said Weber, a European Central Bank Governing Council member.
The summit is the third since the global economic crisis began, but in recent months there have been signs of recovery as a number of countries have emerged from recession.
The US federeal reserve on Wednesday said that growth had returned to the world's biggest economy.
But Dominique Strauss-Kahn, the head of the International Monetary Fund (IMF), warned against complacency and urged the G20 leaders to keep their economic stimulus plans in place.
"Once the fire is out, there's water everywhere, it has to be mopped up," he told Europe 1 radio.
"In Pittsburgh, we have to say, there are still fires to be put out, we'll see later how to do the mopping up."