California’s Air Resources Board has proposed tripling electric vehicle (EV) sales in the state over the next four years to 35% of all new vehicle purchases by 2026, with an aggressive goal to phase out sales of gas-powered cars until 100% of new car sales are electric, hydrogen-powered or plug-in hybrids by 2035, according to a report by AP.

The goal requires a steep increase from 2021 when only about 12% of all cars sold in the state were zero-emission. Of the 26 million cars currently on California’s roads, only about 1 million are zero-emission.

The proposal still requires approval including via a state review process that is expected to take months as well as from the U.S. Environmental Protection Agency. The Biden Administration gave California back the power to set its own vehicle emissions standards under the Clean Air Act.

To accommodate the rapid expansion of EV sales, California also will need to ramp up its supply of EV charging stations. The state has a goal of increasing its fleet of charging stations to 250,000 by 2025, but currently fewer than 80,000 stations exist in public locations.

Some 11% of all new passenger car sales in the U.S. take place in California, giving the state major influence over the auto market, AP reported. A group representing the auto industry told AP that meeting the requirements of the proposal would be “extremely challenging.”

Currently nine states follow California’s zero-emission vehicle rules, which sets rules through model year 2025, with more states planning to join in coming years. If California’s plan is approved, other states could decide to follow suit. New York has also set a goal to phase out gas-powered vehicles by 2035. And the state of Washington passed a bill in March requiring all new vehicles sold in the state to be electric by 2030.