Fears mount that Murkowski will torpedo car emissions deal

They may not be the most natural of environmental campaigners, but in a surprise reversal US car firms could prove crucial in the fight to stop Republicans stripping the Environmental Protection Agency (EPA) of its right to legislate carbon emissions.

Republican senator Lisa Murkowski is widely expected to move forward next week with her controversial plan to seek a motion of disapproval in Congress that would, in effect, reverse the EPA's recent ruling that carbon emissions constitute a health risk and can therefore be regulated under the existing Clean Air Act.

However, despite having secured support from a number of business groups, the move could face opposition from the auto industry after it emerged that the motion could reignite a long-running row over national vehicle emission standards, raising the prospect of different fuel-efficiency rules in different states.

According to a letter sent to Democrat senator Diane Feinstein by the Department of Transportation, overturning the EPA's ruling on carbon emissions would stop the agency from implementing the National Fuel-Efficiency standards that were announced by President Obama last year.

The letter – from O. Kevin Vincent, chief counsel at the National Highway Traffic and Safety Administration (NHTSA), the department responsible for fuel economy standards – warned that if the agency were forced to proceed on its own without the EPA's involvement, many of the benefits of national standards would "substantially erode".

He added that stripping the EPA of its powers would also likely drive California and 13 other states to revive their plan to enforce their own tougher emissions standards, which had been dropped following Obama’s announcement of more demanding national standards. Vincent said the move would create confusion, encourage renewed litigation, and drive up the cost of compliance for automobile manufacturers and motorists.

The letter mirrors one sent earlier this week by EPA administrator Lisa Jackson to a group of eight senators, which warned that Murkowski's proposals would "undo a historic agreement among states, automakers, the Federal government and other stakeholders".

Back in September, the Alliance of Automobile Manufacturers and the Association of International Automobile Manufacturers also sent a joint letter to senator Feinstein, signalling their opposition to an earlier effort by Murkowski to challenge the EPA’s ruling.

The move marks something of a reversal for the auto industry, which has consistently lobbied against more demanding fuel economy standards, but is even more fiercely opposed to the prospect of a patchwork of numerous vehicle emissions targets being adopted by different states.

The move came in the same week as opposition to Murkowski’s proposal (which could come to a vote as early as next week) heated up, with nine environmental commissioners from states that had agreed to originally adopt California’s vehicle emissions standards writing to Senate leaders to warn that the resolution would disrupt the rollout of standards that have "been widely praised by the automobile industry, environmental organisations, labour unions, states, the Obama administration, and many members of Congress".

Meanwhile, the chances of the Obama administration's preferred means of regulating carbon emissions through a new climate bill appeared to recede further yesterday after a Reuters' survey of 12 senators revealed continued opposition to the proposed legislation.

The poll of Democrat and Republican senators who are likely to hold key swing votes if the bill is presented before the Senate revealed skepticism that a climate bill could be passed this year.

"The economy has got to be given a major boost, particularly when it comes to jobs. I think that's going to be our focus," senior Democratic senator Carl Levin told the news agency. "And if we can do something on healthcare this year, those two things are going to use up most of the oxygen. So it's hard for me to see how we get to the climate issue."

His comments were echoed by Republican senators Richard Lugar and George Voinovich, both of whom predicted a bill would not pass this year.

The administration has long maintained it will try to pass legislation later this year and is currently awaiting a new compromise version of the bill that is being developed by a bipartisan trio of senators – John Kerry (Massachusetts), Lindsey Graham (South Carolina) and Joe Lieberman (Connecticut).