WASHINGTON — General Motors abandoned President Trump’s battle to nullify California’s fuel economy rules meant to curb global warming, the strongest sign yet that corporate America is moving on from Mr. Trump and adapting to an incoming Democratic administration.
The company also signaled that it was ready to work with President-elect Joseph R. Biden Jr., who has promised swift action to reduce climate-warming emissions in the auto sector.
“President-elect Biden recently said, ‘I believe that we can own the 21st century car market again by moving to electric vehicles.’ We at General Motors couldn’t agree more,” Mary Barra, the General Motors chief executive, wrote in a letter Monday to leaders of some of the nation’s largest environmental groups.
Ms. Barra said her company, one of the largest automakers in the world, was withdrawing its support for Trump administration litigation that seeks to strip California of its ability to set its own, strict fuel economy standards, and she urged Toyota and Fiat Chrysler to do the same.
Ms. Barra also spoke by telephone on Monday with Mary Nichols, California’s top climate regulator, who is a leading candidate to run the Environmental Protection Agency in a Biden administration.
A spokesman for the Trump administration’s E.P.A. appeared unaware of General Motors’ withdrawal of support in the California litigation. “It’s always interesting to see the changing positions of U.S. corporations,” said the spokesman, James Hewitt.
The decision is an abrupt reversal for General Motors, which four years ago was one of the first to push Mr. Trump to loosen Obama-era standards on fuel economy and climate-warming emissions. Ms. Barra met with Mr. Trump in his first weeks in office and urged him to weaken the stringent tailpipe pollution standards that stood as the United States’ largest domestic policy to curb global warming.
Last year — after the administration went even further, revoking the legal authority of California and other states to set tighter state restrictions — G.M., Toyota and Fiat Chrysler intervened on the side of the administration in support of that move.
Ms. Barra’s letter stopped short of backing California’s standards but indicated a realignment is coming.
“We believe the ambitious electrification goals of the President-elect, California, and General Motors are aligned to address climate change by drastically reducing automobile emissions,” she wrote. “We are confident that the Biden Administration, California, and the U.S. auto industry, which supports 10.3 million jobs, can collaboratively find the pathway that will deliver an all-electric future. To better foster the necessary dialogue, we are immediately withdrawing from the pre-emption litigation and inviting other automakers to join us.”