"As part of an ongoing routine audit, Deutsche Bank is working with Russian tax authorities on matters relating to standard business operations that follow normal industry practice," Deutsche's Russian unit said in a statement.

Citing sources, RBC reported that the tax service believes that the bank lowered its taxable income in 2013 and 2014 when it was buying the foreign currency on the domestic currency market and selling it to London's Deutsche Bank.

($1 = 58.1164 roubles)

(Reporting by Alexander Winning; Editing by Katya Golubkova)