Fuji Heavy can reduce its research and development and manufacturing costs by working with Toyota, while GM will be able to pull out of an alliance that is no longer benefiting either GM or Fuji Heavy, Matsumoto said.

The American auto giant and Fuji Heavy have both been struggling with high cost structures and sliding car sales, and there wasn't much synergy in the alliance.

"We've had a good partnership. However both GM and Fuji Heavy came to the conclusion that there were not enough collaborative projects to sustain the alliance and that each of our interests could be better served through a different approach," Troy Clarke, GM group vice president, said in a statement.