WASHINGTON, April 23 (Reuters) - A group of 22 states

led by California and five cities are backing the U.S.

Environmental Protection Agency's new tailpipe emissions rules

after 25 Republican-led states sued last week.

The lawsuit filed Thursday challenges the 2027-2032 model

year EPA vehicle emissions rules that aim to cut fleetwide

tailpipe emissions for cars and light trucks by nearly 50% over

2026 levels in 2032.

California, New York, Michigan, Pennsylvania and other

states sought to intervene in the lawsuit saying they could be

harmed if the EPA could not require future reductions in harmful

vehicle emissions.

"California won't sit back - we're not going to watch

radical Republicans put the profits of big oil over the health

of our planet," said Governor Gavin Newsom in a statement.