President Trump slammed the cryptocurrency market on Thursday, claiming that the digital assets are “not money” and their value is “based on thin air.”

“I am not a fan of Bitcoin and other Cryptocurrencies,” Trump tweeted.

The president criticized the assets for being “highly volatile” and accessible to criminals.

“Unregulated Crypto Assets can facilitate unlawful behavior, including drug trade and other illegal activity,” he wrote.

“Similarly, Facebook Libra’s ‘virtual currency’ will have little standing or dependability.”

The Facebook currency has already grabbed the attention of Fed Chairman Jerome Powell.

He warned Congress on Wednesday that Libra “raises serious concerns regarding privacy, money laundering, consumer protection, financial stability.”

Trump ended his remarks by promoting the US dollar.

“We have only one real currency in the USA, and it is stronger than ever, both dependable and reliable,” he wrote.

“It is by far the most dominant currency anywhere in the World, and it will always stay that way. It is called the United States Dollar!”