BEIJING, May 10 -- Chinese officials this week reiterated their assent to alter their policy of pegging its yuan currency to the dollar but have set no timetable for doing so, a top U.S. trade official said today.

U.S. Treasury Under-Secretary John Taylor told reporters that China assured him changes would be forthcoming, although he allowed that it was a reassurance of previous pledges. Taylor has been in Beijing talking with senior Chinese officials over currency reform part and inflation.

In a news report this morning, Reuters quoted Taylor as saying, "We stressed that flexibility of the exchange rate was an important policy to have in place to prevent the overheating and to prevent inflationary pressures."

Reuters reported that Taylor said Chinese officials pledged changes, although when actions would be taken remains unclear.

"They've always said that there's going to be movement on the exchange rate and that was repeated today," Taylor said. "There's never been a specification of the time and even if I knew the time I couldn't talk to you about the time, it wouldn't be helpful to the markets at all."

China has for years pegged the yuan at about 8.2 per dollar. Critics say that figure is too low and makes Chinese goods artificially cheap when sold abroad.

Several economists and trade associations have lobbied Congress to pressure China to change its curreny policy.