Regulators around the world are growing concerned that stablecoin arrangements will become too-big-to-not-regulate.  For example, the large amount of commercial paper held by a stablecoin arrangement could, in theory, trigger contagion in credit markets if the arrangement unraveled.  

Accordingly, a recent report suggests that regulators are contemplating designation, and subsequent treatment, of such arrangements as systemically important, an approach that might establish a regulatory backstop while national regulators, such as the U.S. Securities and Exchange Commission, and local legislatures, like the U.S. Congress, grapple with more granular characterization and prescriptive regulation of stablecoins (and digital assets more generally). 

See the Consultative Report of IOSCO and the Committee on Payments and Markets Infrastructures at CR03/2021 Application of the Principles for Financial Market Infrastructures to stablecoin arrangements (iosco.org)