As reported by The Wall Street Journal, the proposal, which would require a public comment period, would require carmakers to road-test vehicles to verify mileage claims posted on window sticker prices.

The move follows the recent restatement of EPA ratings on some cars and light trucks by Hyundai, Kia and Ford after claims that they were inflated.

‘Some auto makers already do this, but we are establishing a regulatory requirement for all auto makers,’ Chris Grundler, director of the EPA’s Office of Transportation and Air Quality, told The Journal.

The publication added that the proposal would also make it difficult to manipulate lab results to achieve higher mileage ratings.