Still, the agency’s regulations would take months to write and years to become fully effective. Meanwhile, Congress is already starting work on energy and climate legislation, though without significant guidance from the White House, at least in public.

Carol M. Browner, the White House coordinator of energy and climate policy, issued a surprisingly bland statement last week when two top House Democrats unveiled a far-reaching plan to cap greenhouse gases and move the nation toward an economy less dependent on carbon-rich fuels like coal and oil.

Ms. Browner stopped short of endorsing that plan, issued by Representatives Henry A. Waxman of California and Edward J. Markey of Massachusetts, saying instead that Mr. Obama “looks forward to working with members of Congress in both chambers to pass a bill that would transition the nation to a clean-energy economy.” She gave little clue as to what she and the president believe such a measure should say.

At an international climate conference in Germany that ended Wednesday, some delegates said they were disappointed in the Obama administration’s lack of robust leadership. The explanation offered by Jonathan Pershing, a leader of the American delegation, was that the administration was waiting to measure the American technological and political capacity to address climate change and was looking to Congress to set specific targets for reducing carbon pollution.

Business lobbyists welcome the White House’s go-slow approach, saying the issue is too complicated and too costly to be rushed, especially in a recession.

“We have not until now had a national debate on a climate change proposal, period,” said Karen A. Harbert, a former senior Energy Department official who now heads the United States Chamber of Commerce’s energy institute. “That has to happen for any piece of legislation to achieve broad support across the country.”

Ms. Harbert and other business lobbyists also welcomed the administration’s hesitancy to undertake regulation of climate-altering gases under E.P.A. authority, saying the matter should be fully aired before Congress so that all interests and regions could be heard.