BERLIN (Reuters) - Volkswagen’s premium carmaker Audi aims to phase out combustion engines and offer only electric cars in 10 to 15 years, at the latest, German weekly WirtschaftsWoche reported, citing no sources. The company is currently working on a concrete time plan and expects to have target dates in the coming months for the phase-out at individual plants, it said. It cited Audi Chief Executive Markus Duesmann as saying in an interview that “protection of the environment and economic success go together well”.