FRANKFURT, Aug 13 (Reuters) - Austrian investor Rene Benko has been asked to take over loss-making German department store chain Karstadt, Austrian magazine Format reported on Wednesday.
It quoted Benko as saying that he had been called on "to help by replacing (Nicolas) Berggruen as the owner" of Karstadt. The report did not say who approached Benko.
Billionaire Berggruen rescued Karstadt from insolvency in 2010, but he has come under fire from German unions and media for not investing enough in the chain, allowing rival department store group Kaufhof to take market share.
Last month, Karstadt's chief executive Eva-Lotte Sjostedt stepped down after only five months in the job, sparking fresh speculation that Berggruen could sell Karstadt to Benko for a symbolic price.
Format said Benko's investment vehicle Signa was likely to strike a deal and a decision would be made before the end of August, without saying where it got the information.
Berggruen's holding company had no immediate comment, and Benko was not immediately available.
Last year Berggruen sold 75.1 percent stakes to Benko in both Karstadt's separate premium department store business and its sportswear and equipment outlets. ($1 = 0.7483 euro) (Reporting by Maria Sheahan, with additional reporting by Matthias Inverardi in Duesseldorf and Angelika Gruber in Vienna; Editing by Susan Fenton)