The strong comments from the most powerful US financial regulator underscored the growing regulatory hurdles facing the proposed cryptocurrency, which has drawn scrutiny from policymakers globally.

“Libra raises many serious concerns regarding privacy, money laundering, consumer protection and financial stability”, Powell said during his semi-annual testimony on monetary policy before the US House of Representatives Financial Services Committee.

“I don’t think the project can go forward” without addressing those concerns, he added later.

Powell said any regulatory review of the project should be “patient and careful”. He noted that existing rules do not fit digital currencies.

“It’s something that doesn’t fit neatly or easily within our regulatory scheme, but it does have a potentially systemic scale”, he said. “It needs a careful look, so I strongly believe we all need to be taking our time with this.”

Facebook spokeswoman Elka Looks said in an email that the plan is still in its early days.

 “This is why we along with the 27 other Founding Members of the Libra Association, made this announcement so far in advance so that we could engage in constructive discourse on this and get feedback.”