Musk says may form holding company for Tesla, SpaceX

Musk, answering questions at automotive website Jalopnik.com on Thursday, said capital could not be moved between publicly traded Tesla and SpaceX, but he was interested in the idea of a holding company.

"Am starting to consider whether it would make sense to create a parent corporation that would own the stock," Musk wrote. "Not sure if that is feasible or sensible, but am thinking about it."

Tesla just launched its second electric car, the Model S sedan, which is expected to provide 90 percent of the company's revenue this year. The base price of the car is $57,400.

In May, SpaceX sent the first privately developed ship into space to dock with the International Space Station.

Musk, the inspiration for Robert Downey Jr's Tony Stark character in "Iron Man," also founded online payments site PayPal, now part of eBay . He has said in the past that an initial public offering for SpaceX may eventually happen.

Tesla has plans for the Model X crossover utility vehicle in 2014 and a smaller sedan code-named Gen III in 2015, and Musk said the company will eventually build an electric supercar.

"We will do an electric supercar at some point," he said. "But it is more important to the world that we do an affordable electric car. Hopefully, we will get to an electric supercar in four to five years."

Musk, who predicted there would eventually be electric race cars, also said he has had in mind an idea for a supersonic electric jet for about four years.

(Reporting By Ben Klayman in Detroit; editing by John Wallace)