Ghosn sketches 'massive' plans for Mitsubishi

At the auto show here, Ghosn said he is confident legal and government authorities will approve the $2.2 billion acquisition of a 34 percent ownership stake in Mitsubishi by year end.

And then it will be off to the races.

"This is not a deal where we say, 'OK, we made the deal, now let's think what we can do together," he told reporters. "No. The day we announce the deal, we're going to tell you exactly what we're going to do together. And it's massive. It's massive between Mitsubishi and Nissan. And also, it may be very significant between Renault and Mitsubishi."

He said that plans have not been worked out specifically for how the three automakers will work together in the U.S. But he said the potential is great.

"We will have to dig more in the U.S.," he said. "But when you talk about purchasing, engineering, platforms, engines, plug-in hybrids — it's massive."

Nissan and Mitsubishi already have vehicle-sharing deals. For example, Mitsubishi supplies Nissan with small cars for Japan.

But Ghosn said he envisions something more far-reaching. He wants to make Mitsubishi part of the global Renault-Nissan Alliance, which for 17 years has linked the two companies in purchasing, management, vehicle development and r&d.

"Mitsubishi in this case will join the alliance," he said. "The alliance is about developing synergy. We know that there are a lot of synergies with Mitsubishi and strategically we have a lot of connection."

For now, the prospects for a Mitsubishi-Nissan partnership are clearer in markets such as Japan and India than in the U.S. Nissan and Renault do not compete with each other in the U.S., while Nissan and Mitsubishi have competed for decades.

Nissan has been going all out to increase its U.S. market share, while Mitsubishi has struggled to maintain its share in the country.

In April, Mitsubishi admitted to manipulating test data to report higher fuel-economy claims on certain vehicles. That scandal resulted in the resignation of the automaker's president, Tetsuro Aikawa. The crisis triggered the opportunity for Nissan to step in to take control of Mitsubishi.