SACRAMENTO, Calif. — California is spending $500 million to put an additional 1,000 electric school buses on the road as federal cuts and freezes paused efforts in other states to replace aging diesel-fueled fleets that are more polluting.

Gov. Gavin Newsom’s office announced Wednesday that 1,000 zero-emission school buses and related charging infrastructure will be provided to over 130 rural, low-income and disadvantaged school districts. The state grants add about 500 more charging stations for school buses to more than 200 stations already in operation in districts.

The expansion contrasts efforts in other states that were hampered by the uncertainty over federal funds. For months, more than 500 districts nationwide were waiting on around $1 billion from the Environmental Protection Agency to cover more than 3,400 electric buses, sparking panic and confusion. Some districts delayed or canceled their purchases.

California has the largest fleet of electric school buses in the country after pumping more than $1.3 billion into such efforts and funding more than 2,300 of the buses. Of those, 1,100 are already in use and some districts are 100% electric.

“California is committed to continuing efforts to reduce children’s exposure to toxic diesel pollution through the deployment of zero-emission school buses,” Liane Randolph, chair of the California Air Resources Board, said in an email. The board helps lead the state’s efforts on climate change and oversees air pollution control efforts. “State funding is especially critical as schools grapple with the rollback of federal support.”

In California, the efforts are funded primarily by proceeds from its cap-and-trade program. The program caps carbon emissions and requires polluters to obtain permits for each ton of carbon they release.

The buses are key to California’s climate goals to reach carbon neutrality by 2045. By 2035, nearly all new public school buses will be required to have zero emissions.

California, a U.S. trendsetter on climate policy, has approved policies over the years to limit emissions from cars, lawn mowers, trucks and trains. But some of those measures have faced threats.

A new executive order from President Donald Trump states his Department of Justice will go to court against state climate change laws aimed at reducing planet-warming greenhouse gas pollution from fossil fuels.

Newsom has accused Trump of turning back the clock on climate-friendly policies and said his state’s efforts to reduce pollution won’t be derailed.