(ANSA-AFP) - FRANKFURT AM MAIN, SEP 2 - German automotive giant Volkswagen said Monday it could close production sites in Germany, as the auto industry struggles to manage rising costs. "In the current situation, even plant closures at vehicle production and component sites can no longer be ruled out," Volkswagen said in an internal memo sent to employees and seen by AFP. Europe's largest auto manufacturer remained committed to Germany as a "business location" but "headwinds have become significantly stronger", VW brand CEO Thomas Schaefer was quoted in the document as saying. The challenging conditions meant "we must now step up our efforts" to secure the long-term success of the company, Schaefer said in the note sent to employees. (ANSA-AFP).