Rising market prices underscore the need for Dodd-Frank Actderivatives rules to curb speculation in commodities such as oil,gold and natural gas, Commodity Futures Trading Commission ChairmanGary Gensler told lawmakers.

“Though the CFTC is not a price-setting agency, rising pricesfor basic commodities highlight the importance of having effectivemarket oversight,” Gensler wrote in response to a May 11 letterfrom 17 senators seeking a CFTC plan for curbing crude-oilspeculation. Gensler's letter said he was writing on behalf ofCommissioners Michael V. Dunn and Scott O'Malia.

Regulators and lawmakers have attempted to rein in speculationsince 2008 amid concern that investors contributed to oil's rise toa record $147.27 a barrel. The CFTC has proposed so-called positionlimits in agricultural, metals and energy derivatives, underrulemaking authority granted by Dodd- Frank, the regulatoryoverhaul enacted last year.