Elon Musk, the CEO of Tesla.

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Elon Musk, Tesla CEO, said Sunday the company will resume Bitcoin transactions once it confirms the miners are consuming a reasonable amount of clean energy.

“If there is confirmation of reasonable (~ 50%) clean energy consumption by miners with a positive future trend, Tesla will allow Bitcoin transactions again.”

Musk responded to comments from Magda Wierzycka, CEO of South African wealth manager Sygnia, who said Musk’s tweets about Bitcoin prices were “market manipulation” and should have sparked an investigation by the US Securities and Exchange Commission.

Tesla announced in an SEC filing in February that it had purchased $ 1.5 billion worth of Bitcoin and announced it would accept Bitcoin as a payment method for its products.

However, the electric car maker stopped buying a car with Bitcoin in mid-May because of concerns about how cryptocurrency mining, which requires banks with powerful computers, is contributing to climate change.

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“We are concerned about the rapidly increasing use of fossil fuels in Bitcoin mining and transactions, especially coal, which is the worst emissions of all fuels,” Musk said in May.

On Sunday, Musk denied Wierzycka’s allegations of market manipulation, stating that “Tesla sold about 10% of its Bitcoin holdings” to confirm that BTC could easily be liquidated without moving the market, “he said of” digital assets “related to this helped reduce operating losses by $ 101 million, the company said on its income statement.

Musk’s comments on social media about cryptocurrency often make prices soar or decrease, but seemed to have little immediate impact on Sunday. Overall, Bitcoin prices rose about 8% over the course of the day.