A key Republican lawmaker declined to back a plan by Senate Democrats to slow the growth of U.S. greenhouse gas emissions, casting doubt on whether the Senate can muster enough votes on Tuesday to approve a climate change plan.

As part of its debate of a broad domestic energy supply bill, the Senate is expected also to consider proposals that would address U.S. industry's emissions of carbon dioxide, a heat-trapping gas linked to global warming.

Pete Domenici of New Mexico, chairman of the Senate Energy Committee, last week said he might co-sponsor Democrat Jeff Bingaman's plan to slow the growth of U.S. carbon emissions with an emissions trading program beginning in 2010.

But late Monday night, Domenici announced in a brief statement that he would not support the measure.

"This is just too tough to do quickly," Domenici said, adding that he believes some action on climate change is needed.

"I expect we will have a series of hearings and I hope we can reach some sort of accommodation on all aspects of a climate proposal. But that will take time," he said.

Domenici refused to break ranks with the White House on climate change, after meeting with Vice President Dick Cheney last week and fellow Republican lawmakers on Monday.

The Bush administration opposes any form of carbon dioxide limits, preferring voluntary measures by utilities, manufacturing plants and other emitters. President Bush in 2001 pulled the United States out of the 1997 Kyoto Protocol, citing its economic cost.

The plan proposed by Bingaman is based on recommendations from a bipartisan energy study.

The approach aims to slow the growth of U.S. greenhouse gas emissions by linking them to U.S. economic growth. It would create a trading program with a pool of emissions permits that would shrink about 2.4 percent annually beginning in 2010.

Domenici's support could have changed the calculus for Senate action on climate change. The chamber is expected to debate several climate change amendments this week, including one calling for strict, mandatory limits on emissions.

Before taking up Bingaman's plan, the Senate will consider a stricter option from Republican John McCain and Democrat Joseph Lieberman that would require an outright cut in U.S. carbon dioxide output to 2000 levels by 2010.

The McCain-Lieberman plan, which was defeated in the Senate nearly two years ago with a 55-43 vote, would also create a program for companies to buy and sell carbon emission allowances.

The Senate debate on climate change proposals comes as the Bush administration prepares to attend a Group of Eight meeting early next month. British Prime Minister Tony Blair, who will lead the meeting, said he wants to launch an action plan for rich nations to fight global warming.

The Senate is on track to approve the broad energy package this week with some $14 billion in tax incentives over ten years to encourage more domestic production of oil, natural gas, coal, nuclear and alternative energy.

The U.S. House earlier this year approved its version of an energy bill, which does not include any provisions to reduce greenhouse gas emissions.

© Copyright 2005 Reuters Ltd

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