Tesla CEO Elon Musk said at the Detroit Auto Show this week that the automaker wants to build new factories in China and Europe and is mulling over the idea of a second U.S. plant.

The new factories would likely be built after the automaker's current factory in Fremont, California reaches full annual production of 500,000 in 2020. Musk said the second U.S. plant would likely be located somewhere "closer to the East Coast."

Two years since his last trip to Detroit, Musk spoke during a press conference in the Motor City on Tuesday, where he added that Tesla should be the first automaker to market a fully self-driving car in five or six years. Autonomous vehicles made by any automaker would likely have to wait for regulatory approval another six to seven years however.

Though Musk has repeatedly said he plans to stay with Tesla "forever," he may step down as CEO once the company's next model the $35,000 Model 3, launches in 2017 to pursue other ventures.

Telsa also expects to boost production of electric vehicles to "at least a few million a year" no later than 2025 from fewer than 40,000 last year, Musk said at the Detroit Auto Show.

When asked if Tesla would consider building an assembly plant in Michigan, where Tesla is banned from selling cars, Musk said that it is "not out of the question."

"Maybe Michigan shouldn't stop us from selling cars here," he said, according to Automotive News. "That would be a nice gesture."

Tesla sold 33,000 Model S sedans last year. Tesla's stock soared 48% in 2014 to finish the year at $222.41

Auto World News is on the ground and covering the 2015 North American International Auto Show. Stay with us this week for up-to-the-minute coverage of all the action in Detroit, and follow us on Facebook and Twitter.

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