German automaker Volkswagen (VOWG_p.DE) may end up buying back some cars affected by the emissions scandal, its chief executive told CNBC in an interview. “In some cases it’s very easy to repair the cars, in other cases it’s very expensive and in that case we have to negotiate whether it would be better to bring back some of the cars to Volkswagen,” Matthias Mueller told CNBC at the Detroit auto show on Monday. Some U.S. regulators and lawmakers have said VW may have to buy back older models.