European Commission President Ursula von der Leyen arrives for a College meeting of commissioners in Brussels on May 6. | AFP-JIJI

On the 13th floor of the Berlaymont building in Brussels, Ursula von der Leyen has built a presidential operation that exerts control over every aspect of what goes on inside the European Commission.

Her tight-knit group of advisers has a grip on the day-to-day operations of the European Union’s executive arm as von der Leyen sidelines almost all but her inner circle and micromanages the mammoth organization. A big problem, according to people with direct knowledge of her working style, is that this is spreading her office thin and means less focus on her core economic responsibilities.…