WASHINGTON, March 18 (Reuters) - The U.S. Energy

Department (DOE) on Tuesday is set to unveil final rules that

will significantly soften its proposal that would have slashed

electric vehicles' (EV) mileage ratings to meet government fuel

economy requirements in 2027, sources said.

In April 2023, the Energy Department proposed rules that

automakers said would "devalue the fuel economy of electric

vehicles by 72%" in 2027 and lead to significantly higher

Corporate Average Fuel Economy fines for some automakers.

The final rule will gradually reduce EV mileage ratings

through 2030 and by 65% in total giving automakers more time to

adjust, the sources said.