The World Bank chief has compared cryptocurrencies to Ponzi schemes, adding his criticism to a slew of international concern about the potential impact of digital currencies.
"In terms of using Bitcoin or some of the cryptocurrencies, we are also looking at it, but I'm told the vast majority of cryptocurrencies are basically Ponzi schemes," World Bank Group President Jim Yong Kim was quoted by Bloomberg. "It's still not really clear how it's going to work."
Bitcoin transactions continue to take incredibly long and the volatility in the price means that the currency remains unreliable for the vast majority of purchases.
The World Bank's criticism comes off the back of the South Korean government's decision to ban bitcoin trading as well as an expose of significant fraud by Japanese authorities.
The bitcoin price skyrocketed at the end of last year but the currency has since lost two-thirds of its value.