A hydraulic circuit designed for a hybrid vehicle provided with a hydraulic machine (22) and a pump (20) linked to a transmission (4) driving the wheels of the vehicle, said machine and said pump being linked together in order to allow direct exchanges of fluid that take place in a very high pressure circuit (42) not comprising a pressure accumulator, characterized in that the very high pressure circuit (42) comprises safety means (110) which, in case of overpressure, discharge the fluid to a limited pressure circuit (40) provided with a pressure accumulator (46).