Elaborating on an earlier proposal, three U.S. senators on Thursday issued a "framework" for drawing up bipartisan climate legislation.
The framework provided only a broad view of what a compromise bill would include with details to emerge early next year.
"We would like to underscore the fact that the framework we are releasing today is a starting point for our negotiations going forward," said Sen. John Kerry, a leading Democrat. He was joined by independent Sen. Joe Lieberman of Connecticut and Republican Lindsey Graham of South Carolina.
The three senators have been working on a bipartisan approach for months, one that would also bolster nuclear power and offshore drilling. Their approach reflects a widespread view that the climate bill that advanced out of the Senate environment committee in early November would need to be significantly revised for any hope of getting bipartisan support from at least 60 senators.
White House Press Secretary Robert Gibbs said in a statement that the framework released "is a positive development toward reaching a strong, unified and bipartisan agreement in the U.S. Senate."
Gibbs said the passage of comprehensive energy legislation was essential to the president's other efforts to build a new energy foundation.
The new framework would ease back requirements for early reductions of greenhouse gases. It calls for cuts of 17 percent by 2020, instead of 20 percent, similar to reductions already approved by the House and what President Barack Obama will call for at an international climate conference in Copenhagen.
The blueprint's release also was timed to give American delegates at the Copenhagen climate talks, now under way, additional ammunition in their argument that the U.S. is taking climate change seriously and that Congress is making progress — although at a glacial pace — on reducing heat-trapping greenhouse pollution.
No Republican senator has endorsed the legislation Democrats pushed out of the Environment and Public Works Committee, although Graham supports the need to address climate change and mandatory reductions in greenhouse gases.
The revised proposal will "a send a strong message to the world gathering at Copenhagen. That message is the United States is committed to addressing this challenge," said Kerry at a news conference, joined by the two other senators.
But the three acknowledged they are nowhere near getting the votes needed to overcome a certain Republican delaying tactic on any climate legislation. "We don't have 60 votes," said Lieberman, referring to the number of votes needed to bring legislation to the floor of the 100-member Senate.
Graham said the commitment to expand nuclear energy and open new opportunities for new oil and gas drilling both on shore and on the Outer Continental Shelf is hoped to attract additional support from Republican senators.
The senators said the bill would include tax credits and a substantial increase in government loan guarantees for building nuclear reactors as well as some streamlining of the reactor permitting process. Currently loan guarantees for new reactors — which can cost $9 billion or more each — are limited to a total of $18.5 billion, and even those have yet to be awarded by the Energy Department.
The legislation also would open the way for offshore oil and gas drilling with the proceeds shared between the federal government and nearby states. Where to drill and how much revenue will be shared with states will depend on negotiations on the bill, said Graham.
The outline embraces the so-called cap and trade approach in the existing Senate climate bill in which the government would limit greenhouse gas emissions from power plants and other industrial facilities, but allow the trading of emission allowances to ease the cost of compliance. Opponents widely have likened cap and trade to an energy tax, saying it will boost energy prices for consumers, prompting Senate sponsors of the bill to avoid the phrase whenever possible.