BERLIN, July 21 (Reuters) - A Taliban spokesman quoted by Western media as announcing the killing of two German hostages in Afghanistan does not speak for the kidnappers, a German newspaper reported on Saturday. Germany's Bild am Sonntag newspaper quoted unnamed German government sources as saying Qari Mohammad Yousuf, who announced the killings, did not speak for the hostage takers. German intelligence sources confirmed for Bild that the spokesman had nothing to do with the kidnappers, it said. "He may be someone trying to take advantage of the situation," Bild said in a preview of an article to appear on Sunday.