President Donald Trump’s nominee to head the Environmental Protection Agency has said he wants to review tough federal gas mileage and greenhouse gas standards for 2025 that were set up under President Barack Obama. One effect of a rollback could be to slow down the auto industry’s momentum toward producing affordable electric cars.

In a meeting with President Trump in late January, auto executives asked him to ease up on the Corporate Average Fuel Economy (CAFE) standards. And EPA nominee Scott Pruitt — who as Oklahoma attorney general repeatedly sued the EPA to overturn various regulations — said in his confirmation hearings he wanted to review how the Obama EPA set those standards.

With an easing of the standards, auto companies could narrow their efforts to improving traditional internal combustion engines with less need to refine and sell electric vehicles. “Loosening of the 2025 CAFE standards would unquestionably allow automakers to refocus their attention on combustion-only vehicles at the expense of affordable electric cars,” said Michael Harley, executive analyst for Kelley Blue Book.