Chinese state banks are stepping up compliance on funding to Russian clients amid threats of secondary sanctions from the U.S., Bloombergreported Tuesday, citing anonymous sources familiar with the matter. Last month, the United States threatened to cut off access to its financial system for foreign banks that back companies targeted for supporting Russia’s defense industry. According to Bloomberg’s sources, at least two unidentified Chinese banks have recently launched reviews of their Russian business involved with cross-border deals. “Banks will sever ties with clients on the sanctions list…