Deutsche Bank AG
The move comes at Ackermann's request in the face of an uphill battle to win shareholder backing for his appointment as supervisory board chairman.
But for Ackermann to take over at the supervisory board without a two-year abstention -- as required by German corporate governance rules -- at least 25 percent of shareholders would need to vote in favour.
Deutsche Bank's nomination committee instead recommended Paul Achleitner, finance chief of Allianz
Achleitner's elevation amounts to an about-turn from plans announced in July and changes the dynamics of Deutsche Bank's leadership structure.
The announcement also comes hours after it emerged prosecutors searched the bank's offices in connection with Ackermann's testimony in a case brought against the bank by the late German media mogul, Leo Kirch.
Kirch and his advisors have been suing Deutsche Bank in various jurisdictions for years in a largely unsuccessful campaign seeking to recoup losses for the collapse of the Kirch media empire.
Munich prosecutors searched executives' offices and the legal department at Deutsche Bank for four days last week, a spokesman for the bank told Reuters earlier, adding the investigation was not completed.
Moves to install Achleitner, the board member for finance at Europe's biggest insurer, were put in motion before the raids became public, a person familiar with the matter said on Monday.
But the latest legal moves by Kirch helped accelerate Ackermann's decision, a person familiar with the CEO's thinking said.
Achleitner will give up his post at Allianz to move to Deutsche Bank.
Plans to install Ackermann as chairman were designed to ensure continuity after investment banking head Anshu Jain and Germany chief Juergen Fitschen take over from Ackermann as co-chief executives in 2012.
According to Deutsche Bank, Ackermann said the extremely challenging conditions in international financial markets and the political-regulatory environment demand his full attention as chief executive.
That leaves him short of time to discuss with shareholders any plans to take the chairman's post, it said.
I have nothing more to add, Ackermann told Reuters on the sidelines of a Frankfurt banking conference on Monday.
With regret, the supervisory board notes and respects this decision, Deutsche Bank said.
Key members of the supervisory board had wanted Ackermann to become supervisory board chairman from May 2012 onward.
Ackermann will be leaving the bank's management board, which he has headed since 2002, after the annual shareholders' meeting in May 2012, the bank said.
The transition process for Juergen Fitschen and Anshu Jain as co-CEOs will take place as planned at the beginning of 2012, it added.
Ackermann, Jain and Fitschen had been nailing down the Frankfurt-based lender's strategy before announcing it to employees at a senior management conference set to take place in Montreux next year.
(Reporting by Edward Taylor and Philipp Halstrick; editing by Maria Sheahan and Andre Grenon)