"FINMA is aware of this international hedge-fund-case, (several banks and locations internationally are involved)," the authority said. "FINMA was informed by the bank and is in contact with it."

Credit Suisse warned on Monday it was facing "highly significant and material" losses to its first-quarter results after the fund, named by sources as Archegos Capital, defaulted on margin calls.

(Reporting by John Revill; Editing by Michael Shields)