[Bipartisan U.S. Senators Urge Treasury to Preserve States' Stablecoin Regulatory Authority Under the GENIUS Act] According to The Block, a bipartisan group of U.S. senators led by Senator Cynthia Lummis has sent a letter to the Treasury Department, urging it to preserve states' authority to regulate stablecoins under the GENIUS Act. The act allows stablecoin issuers with a market cap of no more than $10 billion to be regulated by states, provided that state-level rules are 'substantially similar' to federal rules. In April, the Treasury Department released proposed rules outlining broad principles for determining whether state-level systems are 'substantially similar,' but it did not specify a timeline or standards for state-level regulation. In their letter, the senators stated that the lack of clarity 'creates uncertainty for states' and called on the Treasury to issue guidance clarifying the application, review, and certification processes for state-level systems. Last week, the New York State Department of Financial Services proposed formal rules to align its stablecoin framework with the GENIUS Act.