Treasury Secretary Steven Mnuchin on Monday afternoon said digital-payment ventures need to be held to the same anti-money laundering, or AML, standards as traditional banks. The official said the Trump administration and the Treasury has "very serious concerns" with the growth of cryptocurrencies, including Facebook Inc.'s ambitious digital-payment network currency known as Libra coin, which has drawn white-hot attention to virtual assets of late. Mnuchin said Treasury was concerned with the speculative nature of assets like bitcoin /zigman2/quotes/31322028/realtime BTCUSD -0.91% and its use in illicit activity, including financing terrorism. Mnuchin's briefing on Friday comes after President Donald Trump on Friday, via Twitter, expressed consternation about bitcoin /zigman2/quotes/31322028/realtime BTCUSD -0.91% as well as Facebook Inc.'s /zigman2/quotes/205064656/composite FB +2.12% digital payment venture called Libra coin. Mnuchin's Monday briefing on cryptocurrency regulation also comes a day before Facebook executive Dave Marcus is slated to appear before a Senate committee to discuss Libra. On Friday, Trump tweeted: "I am not a fan of bitcoin and other Cryptocurrencies, which are not money, and whose value is highly volatile and based on thin air," he said. Mnuchin reiterated Trump's comments and said that Facebook has "a lot of work to convince us" that it is complying with U.S. bank regulation. On Monday afternoon, bitcoin prices trading on CME Group were off 8.1% at $10,780.