MILAN, Jan 7 (Reuters) - Stellantis ( STLA ), Toyota ( TM )

, Ford, Mazda ( MZDAF ) and Subaru are

planning to pool carbon emissions with U.S. EV maker Tesla

to comply with European Union 2025 rules, an EU filing

showed on Tuesday.

Volvo, Polestar and Smart are also

planning to pool their carbon emissions with Mercedes,

the same document showed.

If not met, EU 2025 intermediate carbon reduction targets,

or so-called CAFE standards, could cost automakers billions of

euros in fines.

A spokesman for Stellantis ( STLA ) said the carmaker's participation

to the pool would help it meet its EU targets for 2025 "while

optimising our resources".

"At the same time, we continue to focus on developing the

innovative electric and low-emission technologies that are at

the heart of our strategy," the spokesman said.

The other carmakers involved were not immediately reachable

for comment.

Stellantis' ( STLA ) head of European operations, Jean-Philippe

Imparato, last month said that based on EU rules, the group's EV

sales in Europe would have to increase from 12% of the current

total to 21%, with potential fines of 300 million euros ($312

million) for any missed percentage point.

($1 = 0.9606 euros)