Deutsche Bank Co-CEO Anshu Jain warned on Wednesday that additional liquidity measures by the European Central Bank (ECB) would achieve little.
His comments come as markets are increasingly anticipating the launch of a bond buying program at the ECB's monthly policy meeting and announcement on Thursday.
"We're getting to the point where much more won't make a difference," Jain said. Speaking on the sidelines of a banking conference in Frankfurt, Germany, Jain said the group had "excellent momentum" but conceded that challenges linked to low interest rates would be "with us for a long time".
"The reality is, thanks to the ECB's actions which were required, low interest rates are a reality which will not go away any time soon."
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In remarks made to delegates at the conference, Jain warned European banks were losing out in the competitiveness stakes to the U.S. as they contend with increased regulation.
Deutsche Bank is one of many European lenders currently undergoing tough tests carried out by the European Central Bank to see how it would cope with a hypothetical downturn. Results of a so-called Asset Quality Review, part of a broader Comprehensive Review, are due to be published in October. Banks have divested assets and written off bad loans in preparation for the stress tests.
It has faced huge costs related to lawsuits and investigations including the Libor benchmark rate scandal. It has already paid more than 5 billion euros ($6.57 billion) over the past two years in settlements and fines.
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