MUNICH—Volkswagen may have to spend more to deliver its planned transformation, the German carmaker’s supervisory board chairman said, particularly a shift towards autonomous driving. The world’s second-largest automaker, which plans to invest 150 billion euros ($178 billion) in its business by 2025, has repeatedly said that it can fund the transition towards electric vehicles and autonomous driving based on current cash flows. “We are in a phase where substantial free cash flows are being generated. That means we can pay out good dividends as well as comfortably fund our business going forward,” Hans Dieter Poetsch told Reuters at the IAA Munich car show. “But of course we are in an environment in which we cannot rule out that larger sums, for example in the field of autonomous driving, have to be invested,” Poetsch, who is also chief executive of Porsche SE, which is Volkswagen’s largest shareholder. “It is therefore recommendable …