During a virtual event for the Richard Nixon Foundation on Tuesday, billionaire venture capitalist Peter Thiel expressed his worries that China could potentially be using Bitcoin to undermine the U.S.

Thiel, who co-founded PayPal, said that Bitcoin “threatens fiat money, but it especially threatens the U.S. dollar,” and added:

“Even though I’m a pro-crypto, pro-bitcoin maximalist person, I do wonder whether at this point, bitcoin should also be thought [of] in part as a Chinese financial weapon against the U.S.”

Thiel believes that China is elevating Bitcoin to use as a weapon against the dollar because China would like to see two global reserve currencies, rather than the US dollar being the default reserve currency. Chine does not want its renminbi to play the part though, and the use of the Euro in the past did not work either, therefore it is now turning to Bitcoin.

“From China’s point of view, they don’t like the U.S. having this reserve currency, because it gives a lot of leverage over oil supply chains and all sorts of things like that,” Thiel said.

“[If] China’s long bitcoin, perhaps from a geopolitical perspective, the U.S. should be asking some tougher questions about exactly how that works,” he added.

China have recently started trialling a digital version of its currency which currently is in an advanced stage, however according to Thiel, the digital yuan cannot be considered “a real cryptocurrency.” “That’s just some sort of totalitarian measuring device,” he said.