A Senate committee approved a plan Tuesday to increase fuel efficiency standards to an average of 35 miles per gallon by 2020 in a move closely watched by automakers and environmental groups.

The Senate Commerce, Science and Transportation Committee passed the measure on a voice vote. It would raise the nationwide fleet fuel economy average by about 40 percent compared with the current levels of 25 mpg and increase standards by 4 percent a year from 2020 through 2030.

"This is not a perfect bill, but I think we have reached a stage where most parties would say this is fair," said Sen. Daniel Inouye, D-Hawaii, the committee's chairman.

He said the bill would be considered before the full Senate in June.