Citigroup is under investigation by multiple U.S. government agencies, including the Department of Justice (DOJ), Federal Bureau of Investigation (FBI), and Internal Revenue Service (IRS), for its alleged ties to sanctioned Russian billionaire Suleiman Kerimov. The inquiry focuses on Citi's involvement with a trust that manages assets belonging to Kerimov, who has been sanctioned by the U.S. government. This investigation is part of a broader scrutiny of how Russian oligarchs manage and access their assets abroad. Reports indicate that the investigation is intensifying as federal officials seek to understand the extent of financial institutions' connections to individuals under U.S. sanctions.