MILAN (Reuters) -Japanese automaker Mazda ( MZDAF ) has teamed up with its joint venture with China's Changan to pool carbon credits and help avoid carbon emissions fines, an EU document showed.

Several legacy carmakers face potential European Union fines as their shift to electric vehicles (EVs) has been slower than expected. But those with lower shares of EV sales can "pool" their emissions with segment leaders, purchasing credits from them and lowering their overall averages.

EU's fines, which carmakers have said could total up to 15 billion euros ($17.5 billion) for the industry, were initially envisaged to apply to 2025 carbon emission levels. 

However, in March, the European Commission bowed to pressure from car manufacturers and allowed compliance based on their average emissions over 2025-2027.

The pool between Mazda ( MZDAF ) and its 50/50 joint venture with Changan is valid for 2025 and is open to other manufacturers until the end of November.

It adds to four others formed earlier this year, all of them valid for 2025, including ones built around Tesla and Mercedes-Benz.

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