The midsize sedan goes on sale this fall.

Other hybrids charge buyers a premium over the gas version.

Ford's move comes as automakers race to expand their lineups with cleaner and greener vehicles, frugal consumers pay more attention to fuel costs, and the federal government imposes stricter fuel economy standards.

"It's very big news and I give Ford thumbs up for making it happen," said James Bell, executive market analyst for Kelley Blue Book in Irvine, Calif.

Hybrids are becoming increasingly mainstream, Bell said, but with this step, "even the price difference is being washed away."

There are no plans to make the same offer on Ford brand hybrids, said Ford spokeswoman Marisa Bradley.