"The low interest rates are a huge problem for banks, but the ECB's interest rate turnaround should be implemented carefully," the BdB said, adding that the euro zone monetary union had not solved all of its problems yet.

The comments came after German Deputy Finance Minister Jens Spahn told Reuters on Friday that the ECB's expansive monetary policy has numerous side-effects and a "prudent start to the exit" of the stimulus is therefore desirable.

(Reporting by Gernot Heller,; Writing by Michael Nienaber; Editing by Joseph Nasr)