DETROIT (Reuters) - Automakers are weighing in on a new plan by the Obama administration to slightly loosen the U.S. government's proposed fuel economy standards for the years 2017 through 2025, a person familiar with the situation said.

The government introduced the new plan for a corporate average fuel economy standard after encountering resistance from the industry and lawmakers to its initial target.

Under the new proposal pitched to automakers, the White House is now suggesting a CAFE standard of 54.5 miles per gallon by 2025, said the person, who asked not to be identified discussing the ongoing talks.

Initially, the administration's CAFE target was 56.2 mpg. The automakers had been asked to comment on the lowered target by Tuesday, the person said.

Federal officials have been meeting regularly with the automakers regarding the CAFE standards for 2017 through 2025.

The Department of Transportation and the Environmental Protection Agency are jointly working to develop the new standards.

Several automakers declined to confirm the new proposal.

The White House's new proposal includes annual average increases in fuel economy of 5 percent for cars and 3.5 percent for light trucks through 2021, with a 5 percent increase for all vehicles after that, according to the person.

Officials with the White House, as well as with automakers Chrysler, Toyota Motor Corp and Nissan Motor Co could not immediately be reached. Honda Motor Co declined to comment.

In 2009, the Obama administration raised CAFE standards, requiring automakers to boost the average fuel efficiency of their vehicles to 35.5 miles per gallon by 2016.

The administration has publicly said it is targeting a range between 47 mpg and 62 mpg for 2017 and beyond. The CAFE standard in 2010 was 29.2 mpg.

"Ongoing discussions are yielding progress and we appreciate the careful and constructive approach by all parties," General Motors Co spokesman Greg Martin said in a statement. "We are hopeful there is a path forward that greatly improves vehicle fuel economy while preserving customer choice and future industry growth."

The push to boost fuel efficiency has forced automakers to redesign their vehicles and use lighter but more expensive materials. These efforts are likely to raise the cost of vehicles and may pinch automakers' margins.

That has caused resistance from lawmakers in states with a heavy auto manufacturing presence, as well as the United Auto Workers union, which is concerned about lost jobs.

Ford Motor Co spokeswoman Meghan Keck said: "We continue to believe the talks are productive." She added that there are "several issues in flux."

The Wall Street Journal first reported the new target for CAFE standards.

(Reporting by Ben Klayman and Deepa Seetharaman in Detroit, editing by Matthew Lewis)