WASHINGTON — The nation's top regulator of oil trading yesterday announced the creation of a federal task force to study the role of speculators and large institutions' investment practices that critics believe are running up oil prices.

The announcement came as a special advisory committee went before the Commodity Futures Trading Commission to discuss ways to make the oil markets more transparent to reduce concerns that the trading of contracts for future delivery of oil are being manipulated by investors in ways that drive up prices. The CFTC announced in late May that it is investigating whether there has been price manipulation in this year's steep run-up in global oil prices.

Congress is studying measures to quash what many believe is speculative behavior that is pushing up oil prices. The CFTC, which regulates the futures markets, has said it doesn't believe that speculation is to blame, but promised that the task force will take a deep look.

"It is intended to bring together the best and brightest minds in government to aid public and regulatory understanding of the forces that are affecting the functioning of these markets and it will strive to complete its work quickly and make public its results," CFTC Chairman Walter Lukken said. The task force will include representatives from the Federal Reserve, Treasury Department, Securities and Exchange Commission and departments of Energy and Agriculture.

Critics dismissed the task force as a public relations move that won't lower prices.

"That's a great way to appear to be doing something when you are not," said Michael Greenberger, a Maryland law professor and a former CFTC director of trading.

Treasury Secretary Henry Paulson, who led investment bank Goldman Sachs & Co. before joining the Bush administration, suggested yesterday that supply and demand forces alone are to blame for today's record prices, sparking debate. Bart Chilton, a CFTC commissioner, responded that according to Saudi Arabian leaders, today's high prices aren't justified by such market fundamentals "and I think the Saudis know a little bit about the oil markets."