Tesla Inc (TSLA.O) will no longer accept bitcoin for purchasing car, Chief Executive Elon Musk stated on Wednesday, citing long-brewing environmental concerns for a swift reversal in the company’s position on the cryptocurrency.

Bitcoin drops more than 10% after Musk tweeted his decision to suspend its use, less than couple months after Tesla began accepting the world’s biggest digital currency for payment. Other cryptocurrencies, including ethereum, also fell before regaining some ground in Asia trade.

The need of bitcoin to buy Tesla's electric vehicles had highlighted a dichotomy between Musk's reputation as an environmentalist and the use of his popularity and stature as one of the world's richest people to back cryptocurrencies.

Some Tesla investors, along with environmentalists, have been increasingly critical about the way bitcoin is "mined" using vast amounts of electricity generated with fossil fuels.

Musk said on Wednesday he backed that concern, especially the use of "coal, which has the worst emissions of any fuel."