In a recent call with investors, Tesla chief executive Elon Musk has admitted that he is no longer sure about the effectiveness of his proposed minibus.

In Musk’s second century plan, he revealed that a Tesla Minibus would be created in an effort to fight traffic congestion. The executive believed that by making a fleet of small buses, seating between 10 and 12 people, he could battle congestion as unlike normal buses, Tesla’s alternative would accelerate and brake at the same speed as normal cars, rather than holding up traffic like traditional buses often do.

However, speaking to investors, the outspoken executive said electric buses may not be the solution and that his latest tunnelling venture is, reports The Verge.

“I don’t know if the bus thing really makes sense in the shared fully autonomous environment. If it costs less than a bus ticket to make use of a shared autonomy fleet to go wherever you want, point to point, well why don’t you just use that? So I don’t know,” Musk said.

As recently as July 2016, Musk said the Tesla Minibus would be built on the chassis of the Model X but now it seems likely the entire project will be scrapped as according to Musk, traffic congestion “can be fully alleviated with tunnels.”

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