Mercedes boss Toto Wolff is unhappy with the way Formula One's governing body conducted a recent investigation into the performance of Ferrari's power unit.
Ahead of the Monaco Grand Prix the FIA confirmed it was happy Ferrari is operating within the regulations after spending the previous two races looking into the way its Energy Recovery System works. The investigation had been prompted by suspicions that the team had found a way to deliver more than the permitted 120kw of power from its MGU-K, the part of the engine which recovers and deploys energy to the rear wheels.