Tensions rise over China currency

WASHINGTON (CNN) -- The U.S. Treasury Department has issued its strongest warning yet to China over its currency, saying the country could be deemed a "manipulative trade partner" if it does not revaluate the yuan soon."It's our view that the time has come" for China to have more flexible exchange rates, U.S. Treasury Secretary John Snow said Tuesday.China, which uses exchange controls to artificially peg its currency to the dollar, has been the focus of claims by critics in the United States that its prices from exported goods are artificially low.