Bank of England Governor Andrew Bailey expressed concern over rapidly emerging cryptocurrency assets, stating that they could be dangerous for regulated financial firms, while colleagues claimed they may one day be "worthless."

BoE employee Thomas Belsham detailed his reservations regarding cryptocurrencies, contending that the absence of relative value “may even, ultimately, render Bitcoin worthless” in the future.

“The problem is that, unlike traditional forms of money, Bitcoin isn’t used to price things other than itself," he wrote, as reported by The Guardian. "As Bitcoiners themselves are fond of saying, ‘one Bitcoin = one Bitcoin.’ But a tautology does not a currency make.”

Bailey conceded that "[bitcoin] probably isn't a financial stability risk today, but it has all the makings of something that could become one."

Although bitcoin plateaued in November at $67,000, deputy Bank governor Sir Jon Cunliffe told the BBC that "their price can vary quite considerably and they could theoretically or practically drop to zero."

"The point, I think, at which one worries is when it becomes integrated into the financial system," he said. "It's not there yet, but it takes time to design standards and regulations."​

The comments come as politicians have called for increased scrutiny of cryptocurrencies. Representatives from eight leading crypto firms in the U.S., including Coinbase and Bitfury, were asked to testify before Congress regarding "the challenges and benefits of financial innovation."