The probe investigates so-called mirror trades, where the bank's Russian clients bought stocks in roubles, and through simultaneous transactions in London, bought the same stocks in U.S. dollars, thereby moving funds out of Russia without informing authorities, Bloomberg reported.

Last month, The New York State Department of Financial Services (DFS) sought detailed information from Deutsche Bank on possible money-laundering transactions by some of its clients in Russia that could exceed $6 billion (£3.85 billion) in total, a source familiar with the matter told Reuters.

Deutsche Bank declined to comment on this development and referred to its earlier statement published on the issue along with its annual report on July 30. (http://bit.ly/1MIvCE8, page 128)

(Reporting by Ankush Sharma in Bengaluru; Editing by Steve Orlofsky)