PayPal co-founder Peter Thiel warned that the United States should enforce tighter regulations on cryptocurrencies during a virtual roundtable. He also expressed his concern that China is using Bitcoin to corrode the U.S. financial system.

"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 said.

Thiel followed up the statement by expressing his concern that the cryptocurrency will threaten the U.S. dollar. Before making his "financial weapon" remarks, the billionaire venture capitalist explained the role the U.S. dollar plays in America's worldwide leverage and China's opposition to a reserve currency.

"From China's point of view, they don't like the U.S. having this reserve currency because it gives us a lot of leverage over Iranian oil supply chains and all sorts of things like that," Thiel stated.

During the virtual roundtable, Thiel also criticized Google and Apple for being too close to China. To hear Peter Thiel's remarks, view the clip above.