Back in September, we reported that California Governor Jerry Brown was interested in potentially stopping the sale of new vehicles with gasoline engines. At the time, no specific date had been chosen, as state lawmakers were only beginning to explore the idea. But a bill that will soon be introduced would put an end to statewide gas-powered car registrations starting in 2040.

Bloomberg reports that Phil Ting, a California state assemblymember, and chair of the state’s budget committee, plans to introduce a bill that, beginning in 2040, would only allow the DMV to register cars that don’t emit carbon dioxide. That could mean electric vehicles, but it could also mean cars running on hydrogen or other alternative fuels.

“Until you set a deadline, nothing gets done,” Ting said. “It’s responsible for us to set a deadline 23 years in advance.”

 Ting said he plans to present the bill next month when the 2018 legislative session begins

While it would certainly be a controversial move, banning fossil fuel cars already has support from a number of lawmakers. “I’ve gotten messages from the governor asking, ‘Why haven’t we done something already?’” Mary Nichols, head of the California Air Resources Board, said back in September. “The governor has certainly indicated an interest in why China can do this and not California.”

By 2040, France and Britain want to ban the sale of cars powered by gasoline.