While the United States may be slowing its drive to reduce emissions as a nation, California could press for more stringent standards that could end up being as strict those recently planned by some countries.

The nation’s most populous state may propose a plan to ban internal combustion engines, following France and the United Kingdom, Bloomberg reported Tuesday. California Air Resources board chair Mary Nichols told the publication Gov. Jerry Brown, “has expressed an interest in barring the sale of vehicles powered by internal-combustion engines,” in that state.

It would follow a trend California has set since the 1960s when CARB was set up and the state started to create its own air quality and emissions standards to curb some of the worst pollution problems in the Los Angeles area. However, blocking the sale of gasoline- and diesel-powered new cars could radically transform not just a market of 2 million new vehicles per year, but also the market of 13 other states and the District of Columbia that follow California’s emissions standards.

More new cars were sold in 2016 in California alone than in France, and nearly as many as the United Kingdom; both countries announced 2040 targets for internal combustion bans. The state and those that follow its standards contributed significantly to the 17.55 million new vehicles sold in the US last year. Already, California’s zero-emissions mandate has forced nearly every automaker to sell some kind of plug-in vehicle. That has eventually led to nationwide availability of cars such as the Chevy Bolt and Nissan Leaf.

But California, and CARB, apparently have much tougher standards on the horizon, with Nichols telling Bloomberg that there is a need to, “pretty much replace all combustion with some form of renewable energy by 2040 or 2050,” in order to cut emissions by 80 percent from 1990 levels. (These levels are already drastically lower than when the 1970 Clean Air Act was adopted.)

Meanwhile, the EPA last month cracked open the door for automakers to revisit the emissions targets for 2022–2025. While the head of the agency, Scott Pruitt, hasn’t made any changes to the Corporate Average Fuel Economy standards for automakers set by the Obama administration, there hasn’t been a firm message that those regulations will stay, either.

But a number of automakers are unlikely to change their course, as BMW and the Volkswagen Group have already joined Jaguar Land Rover and Volvo in adding electrification to most, or all, of their new vehicles in the next few years. Those companies should be able to meet the standards CARB puts out, and likely pressure other automakers to follow suit.

It may not matter if California is going to charge ahead with stricter standards to clean up its air. And that means it may eventually drag all of the US into an internal combustion engine ban someday.