U.S. Congressman Stephen Lynch (D-MA) expressed concern Wednesday over the possible impact of a central bank digital currency (CBDC), asking Federal Reserve Chairman Jerome Powell to ponder the potential for a tokenized version of the U.S. dollar to wipe out other digital assets.

The Fed has explored the concept of issuing a digital dollar for years, publishing research as far back as 2016. CBDCs are similar to digital tokens in use today like stablecoins—which track the price of a fiat currency—but are managed by their respective governments instead of being issued by private firms on decentralized networks.

Powell indicated it’s unclear to him why any cryptocurrency that isn’t “drawing on the credibility of the dollar” like Bitcoin or Ethereum has any value at all, regardless of a CBDC’s release. He refrained from commenting on how they could possibly be impacted by a CBDC as a result.