China – and China alone – must choose whether its currency should be freed from its artificial dollar peg, according to Tim Geithner, the US Treasury Secretary.

However, speaking after a weekend of controversy over the yuan, Mr Geithner said he remains confident the Beijing authorities will choose to refloat their currency.

His comments come just days after he delayed the planned April 15 publication of the Treasury's semi-annual currency review – which could have branded the Chinese as currency manipulators – and as the US Congress pressures the Obama administration into taking action.

"This is China's choice, it's their judgment to make," Mr Geithner said in an interview on Indian television. "I am confident that China will decide it's in their interest to resume the move to a more flexible exchange rate."

The US is keen for the yuan to float freely so as to reduce the trade gap between the two countries but Beijing has consistently dismissed suggestions that the yuan's artificial position creates an unfair playing field for China's exports.

"The exchange rate is not the main reason behind the US-China trade deficit," said Jiang Yu, a Chinese foreign ministry spokesman, adding that "appreciation is not the solution to rebalance Sino-US trade".