A device for setting the pitch of blades for a turbine engine, including a control system acting on a linkage mechanism and including an actuator having two chambers; —a supply member coupled to a fluid transfer bearing for transferring a pressurised fluid from a main supply source in a fixed frame of reference to the chambers; —an auxiliary supply circuit which is arranged in a rotating frame of reference and is connected to the supply member and to the main supply source, the supply member being configured to: —in normal operation, allow fluid to pass from the main supply source to the chambers and to the auxiliary supply circuit, and—in the event of a break in the supply to the chambers from the main supply source, allow pressurised fluid to pass from the auxiliary supply circuit to the chambers.