A valve assembly comprises an electro-magnetic circuit operable to actuate a valve needle (18). The electro-magnetic circuit comprises a fluid inlet tube (1) and an armature (12) being arranged axially in proximity to the fluid inlet tube (1). The armature is movably arranged on the valve needle (18). Its axial movement is limited in one direction by a protrusion (28) associated to the valve needle (18). An armature spring (30) is fixed to the valve needle (18) and rests on the armature (12) exerting a force on the armature (12) pushing the armature (12) towards the protrusion (28).
