More than 100 members of the US Congress yesterday called on the Obama administration to label China a currency manipulator, in a move that highlighted the pressure on Washington to take a more confrontational stance towards Beijing.

In a letter to Timothy Geithner, treasury secretary, and Gary Locke, commerce secretary, the 130 Congressmen demanded the administration designate China a manipulator when it issues its regular report on currency manipulation next month. They called for countervailing duties to be imposed on Chinese imports. “I have not really seen this level of enthusiasm among members of Congress before,” said Tim Ryan, one of the Congressmen organising the bipartisan letter. “There is a heck of a coalition behind this and the time is right.”

The letter adds to pressure on the Obama administration, which is trying carefully to manage its relationship with China, one of the largest buyers of US government debt, amid fears a rift could unnerve investors and undermine recovery.