FRANKFURT (Reuters) - German lender Commerzbank CBKG.DE has poached a senior executive of its larger rival Deutsche Bank DBKGn.DE to assume the role of chief executive, filling a leadership vacuum after months of turmoil. Manfred Knof, head of Deutsche Bank’s retail business in Germany, will assume the top spot at Germany’s No. 2 lender on Jan. 1. He succeeds Martin Zielke, who resigned this summer in the wake of a revolt led by the private equity investor Cerberus, one of the lender’s largest shareholders who was pressing for big changes at the bank. The appointment allows Commerzbank to move forward with a new strategic plan that was put on hold until a new leader was found. The bank is looking at branch closures and shedding international staff to save costs. Hans-Joerg Vetter, chairman of Commerzbank’s supervisory board since last month, has told employees that the lender is not a “restructuring case, but Commerzbank must become more efficient”. “It needs to increase its revenues, reduce costs, and to question the status quo,” Vetter told employees, according to a transcript seen by Reuters. In choosing Knof, Vetter overlooked two current Commerzbank board members who had been in the running. Commerzbank and Deutsche Bank were in merger talks last year but called them off. Since then, Deutsche Bank launched a broad restructuring that sought to cut nearly 18,000 jobs, while Commerzbank has largely marked time. The initial reaction from one top investor was cautiously optimistic. The focus is now on implementing change, and success will very much depend on the relationship between Vetter and Knof, said the person with knowledge of the investor’s position. Knof will assume office subject to approval from its regulator, the European Central Bank. Knof is an “experienced and highly effective top manager who has proven himself in a wide range of tasks in the financial services industry”, Vetter said. Deutsche Bank’s deputy CEO, Karl von Rohr, will take over Knof’s responsibilities, Deutsche Bank said.