WASHINGTON>> In a concession to automakers and labor unions, the Biden administration intends to relax elements of one of its most ambitious strategies to combat climate change, limits on tailpipe emissions that are designed to get Americans to switch from gas-powered cars to electric vehicles, according to three people familiar with the plan.

Instead of essentially requiring automakers to rapidly ramp up sales of electric vehicles over the next few years, the administration would give car manufacturers more time, with a sharp increase in sales not required until after 2030, these people said. They asked to remain anonymous because the regulation has not been finalized. The administration plans to publish the final rule by early spring.

The change comes as President Joe Biden faces intense crosswinds as he runs for reelection while trying to confront climate change. He is aiming to cut carbon dioxide emissions from gasoline-powered vehicles, which make up the largest single source of greenhouse gases emitted by the United States.

At the same time, Biden needs cooperation from the auto industry and political support from the unionized autoworkers who backed him in 2020 but now worry that an abrupt transition to electric vehicles would cost jobs. Meanwhile, consumer demand has not been what automakers hoped, with potential buyers put off by sticker prices and the relative scarcity of charging stations.

The change in pacing is in response to automakers that say more time is needed to build a national network of charging stations and to bring down the cost of electric vehicles, and to labor unions that want more time to try to unionize new electric car plants that are opening around the country, particularly in the South.

But delaying the most stringent requirements of the rule could come at a cost to the climate, after the hottest year in recorded history.

Postponing the sharp increase in electric vehicle sales until after 2030 would still eliminate approximately the same amount of auto emissions as the original proposal by 2055, according to EPA models. But it would mean the nation would continue to pump auto emissions into the atmosphere in the short run.

Analysts say the current lag in electric vehicle sales is to be expected, as the market for early adopters is saturated.