China renews promises of 'more flexible' yuan

China's central bank governor has renewed promises to ease controversial currency controls - but says change will be gradual.

The official Xinhua News Agency cited Zhou Xiaochuan as saying Friday that the exchange rate of China's yuan will be made "more flexible," but in a "step-by-step" way.

Washington and other governments complain China keeps the yuan undervalued, giving its exporters an unfair price advantage and swelling its huge trade surplus.

Beijing made a similar pledge of more flexibility in June, but the U.S. government says the increase in the yuan's value since then has been too slow.