The Department of Interior found of the 36 million acres leased offshore, only 10 million acres are under active development. Onshore, about 56 percent of the leased areas, or roughly 20.8 million acres, is idled.
"These lands and waters belong to the American people, and they expect those energy supplies to be developed in a timely and responsible manner and with a fair return to taxpayers," Interior Secretary Ken Salazar said in a statement. "We will continue to encourage companies to diligently bring production online quickly and safely on public lands already under lease."
Critics of President Barack Obama's energy policies say he's throwing up roadblocks to domestic energy production. American Petroleum Institute President Jack Gerard said Salazar's assertions are absurd.
"The administration is being willfully misleading when it identifies leases as idle when companies are seeking approvals of plans or permits or fighting lawsuits," Gerard said in a statement.
U.S. Reps. Ed Markey, D-Mass, and Rush Holt, D-N.J., both House energy leaders, said they are introducing legislation that would impose a fee on the oil and natural gas industry for sitting on drilling licenses.