The U.S. Commodity Futures Trading Commission said Tuesday that a key U.S. lawmaker, exchange executives and others will testify next week at the agency's first hearing to discuss possible new rules on speculative position limits and hedge exemptions.

The first hearing, slated for July 28 between 9 a.m. and 1 p.m., will include remarks from Congressman Bart Stupak, D-Mich., who has been vocally concerned about excessive speculation.

Others who will appear include IntercontinentalExchange Inc's (ICE) chief executive, Jeffrey Sprecher, and CME Group's (CME) executive chairman, Terry Duffy.

Additionally, representatives from the Futures Industry Association, Delta Airlines (DAL), the American Public Gas Association and the Petroleum Marketers Association of America will also appear.

The agency said it also plans to hold hearings on the topic on July 29 and Aug. 5, both of which will also run from 9 a.m. to 1 p.m.

CFTC Chairman Gary Gensler said in a statement the agency intends to be "critical" as it looks into "different approaches to regulate the energy markets."

"Though we are initially focused on energy, the commission intends to further review other commodities of finite supply in future hearings," he added.

Earlier this month, Gensler made waves when he announced the agency will consider imposing sweeping limits on trading in oil, natural gas and other commodities.

Additionally, the agency is also exploring whether certain traders - like swap dealers, index traders and exchange-traded fund managers - should be allowed to get around position limits through specially-granted exemptions.

The announcement represented an about-face for the CFTC, which had a reputation for having a more hands-off approach to regulation.

Currently, the CFTC only sets speculative trading limits in certain agriculture markets and allows some traders to exceed those limits if they receive special approvals from CFTC staffers. But the CFTC defers to the exchanges to set limits, if appropriate, in all other commodities, including oil.

The exchanges are not required to protect against excessive speculation, and in energy they only usually impose speculative position limits during the last few days of trading before a contract's expiration.

The CFTC was heavily criticized last year by some, including those in the airline and farming industries, and by lawmakers like Stupak, for not doing enough to keep oil prices in check when they reached record-highs.

Critics blamed excessive speculation, although the CFTC's own economists said they believed the price spikes were due to supply and demand factors. Still concerned about the issue, Stupak most recently pushed to get language into the climate change bill to crack down on speculative trading in the energy markets.

On Tuesday, the CFTC said the hearings will explore a range of topics, including how to apply position limits to index traders, the effect of the limits and what methodology the CFTC should use to calculate position levels.

-By Sarah N. Lynch, Dow Jones Newswires; 202-862-6634; sarah.lynch@dowjones.com