A report issued by the Senate Permanent Subcommittee on Investigations found that 84% of cryptocurrency wallets sanctioned by the United States and Israel in connection with Iran transacted primarily in USDT, a stablecoin pegged to the U.S. dollar that is issued by the cryptocurrency company Tether. In one instance, leaked documents appeared to show an Iranian company purchasing tens of millions' worth of USDT on behalf of the Central Bank of Iran (CBI). Other data from a blockchain analytics firm indicate a decline in the use of USDT by Iran-linked wallets between 2024 and 2026, but the Senate report states that Tether cryptocurrencies were still commonly used by wallets recently sanctioned by the United States, including one linked to the CBI and another used by an Iranian oil sales network. The report was prepared by the subcommittee's ranking member, Senator Richard Blumenthal (D-Connecticut).