That's still the case, he said Monday, but added that if no one else steps forward, he might build a working prototype. That would take three or four years, he said.
As with Tesla and SpaceX, Musk mused, there are bound to be unforeseen technical obstacles down the track.
Follow Justin Pritchard at https://twitter.com/lalanewsman . AP National Writer Martha Mendoza contributed to this report from San Jose, Calif.
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