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

Ali Zaidi, Mr. Biden’s senior climate adviser, declined to discuss the details of the final regulation. But he said in an interview that Mr. Biden’s climate policies, combined with record federal investment in renewable energy, would still help to reach the president’s goal of cutting the country’s greenhouse gas emissions in half by 2030.