Three Japanese automakers said they’re developing internal-combustion engines to support low emissions as they seek to achieve net-zero pollution.

Mazda, Subaru and Toyota announced the project at a press conference Tuesday, saying they’re working to integrate the engine technology with motors, batteries and “other electric drive units.”

They said the more compact engines will use carbon-neutral fuels in order to “decarbonize” ICE.

The effort aligns with Toyota’s resistance to putting all of its power train eggs in one basket, particularly under former CEO Akio Toyoda, who stepped down and took the chairman role last year, though its new CEO, Koji Sato, quickly set the opposite target. The developing technology may be a way to split the difference and achieve carbon neutralily at the same time. It has lately appeared prescient as electric-vehicle adoption has flattened and hybrid sales taken off.

The three automakers said they’ve tested alternative fuels through their racing teams, including liquid hydrogen, and that the new engines would be compatible with those. Toyota said they will seek to integrate the developing technology with electric technology.

“This process has clarified the role that future engines will play in achieving carbon neutrality,” Toyota said in a press release. “With the next generation of engines, the three companies will seek to not only improve standalone engine performance but also optimize their integration with electric drive units, harnessing the advantages of each.”

The companies called their technology “highly efficient and powerful,” and that the more compact engines would make space for improved, more aerodynamic vehicle design, along with greater fuel efficiency.

“Even as Subaru, Toyota, and Mazda compete in the product arena with unique engines and cars, the companies have a shared dedication to achieving carbon neutrality through a multi-pathway approach,” the press release said.