Photo via Gage Skidmore/Wikimedia.

Photo via Gage Skidmore/Wikimedia.

The U.S. Department of Transportation may revise automotive fuel economy standards starting with the 2021 model year and could lower standards through 2025, reports Reuters.

The agency is reviewing the Obama administration's emissions rules a year earlier than initially proposed. In March, President Donald Trump ordered the review, which had been closed in the waning days of the Obama presidency.

The Alliance of Automobile Manufacturers, which represents major automakers, said in a statement that the review "must happen regardless of what future standards are."

The 2022 to 2025 model year rules must be finalized by April of 2018 under a 2011 deal.