California air quality regulators have tightened carbon standards in an attempt to further cut emissions from fuels in the state’s transportation system. The changes, approved at the end of a marathon meeting on Friday, are expected to take effect in the spring of 2025.

Several members of the California Air Resources Board called the rule changes a critical step on climate amid an expected rollback of federal environmental efforts under President-elect Donald J. Trump. However, the complex regulations have spurred political fights this year between various groups. State lawmakers from both parties have criticized the changes for their potential to hike California’s gas prices, which are already among the highest in the nation.

The new restrictions have also triggered a dispute among environmental groups, researchers and industry officials over whether the California program disproportionately benefits the biofuels sector. The California Air Resources Board estimates that the program has eliminated 320 million metric tons of carbon dioxide emissions from gasoline and diesel since it began in 2011, an amount equivalent to roughly 85 percent of the state’s annual greenhouse gas emissions.

The agency is projecting that its tighter restrictions will reduce greenhouse gas emissions by 558 million metric tons between 2025 and 2045 — equivalent to about one and a half times the state’s annual emissions. However, some researchers and environmental groups have raised concerns about the program’s focus on biofuels, arguing that it does not adequately take into account all of the emissions associated with their production.