WASHINGTON – President Obama is hitting back at Republican criticism of his energy policies and his role in controlling gasoline prices.

Obama used his weekly radio and Internet address Saturday to underscore his administration’s work to develop alternative energy sources and increase fuel efficiency.

“I’m going to keep doing everything I can to help you save money on gas, both right now and in the future,” Obama said. “I hope politicians from both sides of the aisle join me.”

He accused Republicans of a “bumper sticker” approach to solving the nation’s energy problems.

It’s a familiar theme — Obama struck many of the same chords during two out-of-town trips last week and during a White House news conference on Wednesday.

“We can’t just drill our way to lower gas prices — not when we consume 20 percent of the world’s oil,” Obama said in the address, recorded during a visit Friday to a Virginia jet engine component plant.

In the Republican weekly address, North Dakota Gov. Jack Dalrymple accused the Obama administration of blocking projects and technology that would allow greater energy production. He singled out the Keystone XL pipeline project, which Obama deferred.

“We cannot effectively market our crude oil domestically without a large north-south pipeline,” Dalrymple said. “North Dakota oil producers were scheduled to feed the Keystone pipeline with 100,000 barrels of crude oil per day.”

Obama said there wasn’t enough time to properly study the project ahead of the deadline forced upon him by Republican congressional lawmakers.

On Thursday, the Democratic-controlled Senate blocked another Republican bid to speed approval of the pipeline, which would stretch from Canada to refineries on the Texas Gulf Coast.

Also Thursday, Republican presidential candidate Mitt Romney said Obama is partly to blame for higher prices.

Gasoline prices paused this week in their march toward $4 per gallon.

After 39 straight days of increases, prices fell nearly a penny from Tuesday to Thursday and held steady on Friday at $3.758 per gallon for the national average. The lull won’t last long, and gas is still nearly 50 cents higher than it was at the beginning of the year.

Despite Romney’s assertions, economists say there’s not much a president of either party could do about gasoline prices. The current increases at the pump have been driven by fears of a war with oil-rich Iran and by higher demand in the U.S. as well as in China, India and other growing nations.

Also, a growing number of former regulators, lawmakers and financial analysts blame excessive speculation for driving up energy prices.

Financial speculators now make up 65 percent or more of the purchasers of contracts for the future delivery of oil. Historically, speculators controlled only about 30 percent of such contracts. They’re making big profits and driving up oil prices by bidding up contract prices, riding the market’s “fear premium” about possible Persian Gulf violence over Iran.

What the speculators are doing is perfectly legal.

Wall Street analysts, Washington lawmakers and consumer groups are calling for the Commodity Futures Trading Commission to curb speculation by imposing limits on how many such contracts any purchaser can buy, but financial lobbies have tied up the CFTC’s effort in federal court. Obama has not indicated that the CFTC should act, to the growing frustration of many Democrats in Congress.