"The proof of work system of validating blockchain transactions, which underpins Bitcoin, is not capable of scaling up to cope with the millions of transactions that would be needed to make the crypto token an effective means of payment."

“The Bitcoin network is not a payments network and it is not a scaling network.”

Bitcoin is still seen by some crypto enthusiasts as a way to conduct everyday transactions.

The 30-year-old billionaire, who has expanded FTX into one of the world’s largest virtual asset exchanges, said an alternative type of blockchain known as proof of stake, or other technological innovations, will be required to create a functional crypto payments network.

His criticisms of Bitcoin underscore serious environmental concerns about the amount of energy needed to run proof of work crypto systems.

FTX has used carbon offsets to compensate for the company’s emission, which Bankman-Fried said was worthwhile but not a complete solution “because you just run out of things to offset at some point”.

“I don’t think that means Bitcoin has to go,” he said, adding that the token may still have a future as “an asset, a commodity and a store of value” akin to gold.