California senators Alex Padilla and Dianne Feinstein in a letter to be delivered to President Joe Biden on Monday called for the new administration to set a firm date for ending the sale of new vehicles powered by internal-combustion engines across the country, according to Reuters.

The senators said to follow the lead of their own state which last September, by executive order, set a date of 2035 for ending sales of new light cars and trucks still fitted with an internal-combustion engine.

They also urged Biden to restore California’s authority to set its own fuel efficiency standards, which the Trump administration moved to revoke in 2019.

Other countries have already made moves to eventually end the sale of vehicles that still produce emissions. The most recent was the United Kingdom which last November said it wants to ban the sale of non-electrified cars by 2030 and eventually ban the sale of all vehicles still with an internal-combustion engine by 2035. That's the same date that General Motors wants to be fully electric by.

The Biden administration has previously indicated a desire to reduce the emissions of the nation's fleet. For instance, Biden has indicated that he wants to replace the 650,000 vehicles in the federal government's fleet with EVs.

He has also ordered U.S. agencies to revisit rollbacks made by the previous Trump administration to Obama-era fuel efficiency standards. Last March, a rule requiring a 5% efficiency improvement per year through 2026 under Obama was reduced to 1.5% under Trump to help automakers save on compliance costs.

In their letter, Padilla and Feinstein said Biden should choose a target falling between the Obama and Trump requirements, which major automakers have already agreed upon for a separate rule in California.

Stay tuned for an update.