An electric drive unit for a motor vehicle, comprising: (a) an electric motor, which is a reluctance motor having a motor housing fixed in non-rotatable manner, the reluctance motor being preferably designed with electronically controlled current supply; (b) a stator of said electric motor, with the stator being mounted in the motor housing and having coil-wound poles; (c) a rotor of the electric motor arranged internally of the stator, with an air gap being present between the pole faces of the stator and the outer periphery of the rotor facing said pole faces of the stator; (d) a planetary gear system having a sun wheel, a planet carrier, planet wheels and a ring gear, (e) the rotor of the electric motor and the sun wheel of the planetary gear system being coupled for torque transmission; and (f) a gear casing of the planetary gear system, the gear casing being attached to the motor housing or - at least in part - being an integral component part of the motor housing, characterized in that (g) the rotor of the reluctance motor is provided in addition with permanent magnets so as to increase the power density of the reluctance motor at higher speeds; (h) that the planet wheels having such a maximum diameter and such axial positioning that an imaginary common envelope cylinder for all maximum diameters of the planet wheels is located radially inside of the winding heads present on an axial side of the stator as well as axially beside the radially outer portion of the rotor adjoining the air gap and that the planet wheels project in axial direction outwardly beyond said winding heads either not at all or with less than 50 % of their tooth width in engagement with the sun wheel; and (i) that the torque transmission connection between the rotor and the sun wheel or the torque transmission connection between the planet carrier and a wheel carrier of the drive unit is adapted to be separated, wherein, for enabling such separation, a ring having a multi-groove profile on the circumference is provided at a place where torque is transmitted between an inner rotatable member and a coaxial outer rotatable member, the ring being axially displaceable between a coupling position and an interrupting position. (a) an electric motor, which is a reluctance motor having a motor housing fixed in non-rotatable manner, the reluctance motor being preferably designed with electronically controlled current supply; (b) a stator of said electric motor, with the stator being mounted in the motor housing and having coil-wound poles; (c) a rotor of the electric motor arranged internally of the stator, with an air gap being present between the pole faces of the stator and the outer periphery of the rotor facing said pole faces of the stator; (d) a planetary gear system having a sun wheel, a planet carrier, planet wheels and a ring gear, (e) the rotor of the electric motor and the sun wheel of the planetary gear system being coupled for torque transmission; and (f) a gear casing of the planetary gear system, the gear casing being attached to the motor housing or - at least in part - being an integral component part of the motor housing, characterized in that (g) the rotor of the reluctance motor is provided in addition with permanent magnets so as to increase the power density of the reluctance motor at higher speeds; (h) that the planet wheels having such a maximum diameter and such axial positioning that an imaginary common envelope cylinder for all maximum diameters of the planet wheels is located radially inside of the winding heads present on an axial side of the stator as well as axially beside the radially outer portion of the rotor adjoining the air gap and that the planet wheels project in axial direction outwardly beyond said winding heads either not at all or with less than 50 % of their tooth width in engagement with the sun wheel; and (i) that the torque transmission connection between the rotor and the sun wheel or the torque transmission connection between the planet carrier and a wheel carrier of the drive unit is adapted to be separated, wherein, for enabling such separation, a ring having a multi-groove profile on the circumference is provided at a place where torque is transmitted between an inner rotatable member and a coaxial outer rotatable member, the ring being axially displaceable between a coupling position and an interrupting position.