Mazda has confirmed that it is still continuing to develop its rotary engine, which last saw production use in the Mazda RX-8.
The rotary engine was removed from Mazda's line-up due to its low efficiency. It wasn't able to meet stricter emissions regulations and it suffered high-fuel consumption for its output.

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If it were to go in to production, the new engine would initially be offered in naturally aspirated form, with turbocharged versions following if testing proved them reliable.
Mazda boss, Takashi Yamanouchi, has stated that research into future rotary engines will continue as long as he works at the company. "The challenger spirit that has made us the world leader in rotary engines is still alive and well at Mazda."