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U.S. warns China against backsliding on currency commitments

WASHINGTON (Reuters) - The United States on Tuesday warned China that any wavering in its commitment to a more market-determined exchange rate would be "troubling," but it said it was not clear if Beijing's yuan devaluation marked such a step.

China's central bank on Tuesday pushed its official guidance rate down nearly 2 percent in what it said was a move to make it more responsive to market forces. The move sent the yuan tumbling to a three-year low.

"While it is too early to judge the full implications of the change ... any reversal in reforms would be a troubling development," a U.S. Treasury official said.

The United States has long pressed China to move more quickly toward letting market forces determine the yuan's value, and the Treasury official did so again on Tuesday.

"We will continue to monitor how these changes are implemented and continue to press China on the pace of its reforms," the official said.

China's move could make its exports more competitive in international markets and give a boost to its economy, the world's second largest, which has shown signs of slowing.

Many U.S. lawmakers have accused China of keeping the yuan artificially weak in an effort to support its exports.

(Reporting by Timothy Ahmann; Editing by Paul Simao)