A stage of variable-pitch vanes for a turbomachine is disclosed. The vanes include internal pivots engaged in corresponding housings of a sectorized internal ring. Each ring sector includes axial orifices for mounting two pins for the radial retention of the ring sector on the internal pivot of a vane. Each pin includes an immobilization device cooperating by shape coupling with a complementary immobilization device of the other pin in order to rotationally immobilize these pins in the orifices in the ring sectors.