Updated President Obama on Tuesday demanded more “cops on the beat” to crack down on oil market manipulation, calling on Congress to increase the federal supervision of oil markets and to provide for larger penalties for those caught manipulating markets.

Standing in the Rose Garden, flanked by Attorney General Eric H. Holder Jr. and Treasury Secretary Timothy F. Geithner, Mr. Obama also chided Republicans who have been calling for increased American production as a way to tamper rising gas prices.

“There are politicians who say if we just drill more, gas prices will come down,” Mr. Obama said. “What they don’t say is that we have been drilling more.”He said no amount of drilling would solve the fundamental imbalance “that we use more than 20 percent of the world’s oil and we only have 2 percent of the world’s oil reserves.”

While gas prices are starting to come down, the nationwide average per gallon is still almost $4 — perilously close to the $5 per gallon that Mr. Obama’s political advisers believe could cripple his re-election run. Meanwhile, Mitt Romney, the Republican presidential front-runner, and other Republican critics of the president have tried to link the president to the high prices at the pump.

Mr. Obama, for his part, has repeatedly criticized oil company tax breaks, calling on Congress to end the subsidies as oil companies have been operating at record profits.The president asked Congress to increase the surveillance and enforcement staff at the Commodity Futures Trading Commission.“We can’t afford a situation where some speculators can reap millions while millions of American families get the short end of the stick,” Mr. Obama said, raising the specter of the Enron financial scandal as an example of what can happen with lax regulation.

The president’s proposal drew quick praise from some energy experts who have been calling for a clamp down on what they see as market manipulation. “President Obama’s proposal will make it harder for Wall Street speculators to drive up oil prices,” said Daniel J. Weiss, director of climate strategy at the Center for American Progress, a research group with close ties to the Obama White House. “If Congress adopted these reforms, they would limit Wall Street speculators’ ability to bid up prices.”

Of course, getting Congress to adopt the changes is a pretty huge caveat; Congressional Republicans have their own energy proposal and many say they don’t believe that market manipulation is the cause of rising gas prices. House Speaker John A. Boehner, Republican of Ohio, is pushing for more domestic oil and natural gas exploration, and a freeze on regulations on refineries.

Republicans quickly criticized the Obama proposal. Senator Mitch McConnell, the Republican Senate leader, issued a statement saying that “today’s proposal by the president probably polls pretty well. But I guarantee you it won’t do a thing to lower the price of gas at the pump. It never has in the past.”A Republican National Committee spokeswoman, Kirsten Kukowski, added, in an e-mail to reporters that “today’s Rose Garden event is just another gimmick — a shiny object to distract from the fact that Obama doesn’t have a solution for gas prices.”