The Bush administration has told key senators that it expects China to revalue its currency in August ahead of a planned visit to Washington by President Hu Jintao in September, according to people familiar with the matter.

Senators Charles Schumer and Lindsey Graham, co-sponsors of a bill that would impose a 27.5 per cent tariff on Chinese imports, agreed to delay a vote on their bill after receiving what they regarded as an assurance that China will move on its currency next month.