Charles Schumer, US senator from the state of New York, is threatening legislation to punish China for manipulating its currency. Tim Geithner, the Treasury secretary, is counselling caution and diplomacy. The White House is concerned about managing its wider relationship with Beijing.

It is all beginning to look somewhat like 2005, when the Treasury secretary was John Snow and George W. Bush was president. Back then, Mr Snow's repeated insistence that a move towards a flexible exchange rate was imminent was vindicated in July when the renminbi undertook a small revaluation and was then permitted to crawl slowly higher within a trading band.

The recent apparent rapprochement between the US and Chinese administrations, underlined by Mr Geithner's surprise meeting with Wang Qishan, China's vice-premier, later this week, suggests a repeat move in the next few months.