A steam turbine with a plurality of expansion stages, the steam turbine comprising: - an inner casing housing at least said at least one expansion stage (261, 262), - an outer casing surrounding said inner casing, - a row of stator blades (221, 222) upstream of said at least one expansion stage (261, 262, 263), the stator blades (221, 222) of the row having angular positions controllable during operation of the steam turbine, and - an actuation assembly arranged to rotate the stator blades (221, 222) of said row, the actuation assembly (280, 290) comprising an actuation mechanism, a plurality of transmission devices (285, 286) and a command rod, wherein the command rod is arranged to command the actuation mechanism, wherein the transmission devices (285, 286) are arranged to transmit rotation movements from the actuation mechanism to the stator blades (221, 222) of said row, wherein the actuation mechanism is positioned between the outer casing and the inner casing; wherein the plurality of transmission devices comprises a plurality of actuation rods, wherein each of said stator blades has a spanwise direction, wherein each actuation rod is rigidly coupled to a respective stator blade and extends parallel to said spanwise direction, characterised in that each of the actuation rods of said plurality has an axial rod hole whereby a first rod end and a second rod end are fluidly connected, wherein each of the stator blades of said row has a vane hole whereby a first vane end and a second vane end are fluidly connected, and wherein said rod hole is fluidly connected with said vane hole. - an inner casing housing at least said at least one expansion stage (261, 262), - an outer casing surrounding said inner casing, - a row of stator blades (221, 222) upstream of said at least one expansion stage (261, 262, 263), the stator blades (221, 222) of the row having angular positions controllable during operation of the steam turbine, and - an actuation assembly arranged to rotate the stator blades (221, 222) of said row, the actuation assembly (280, 290) comprising an actuation mechanism, a plurality of transmission devices (285, 286) and a command rod, wherein the command rod is arranged to command the actuation mechanism, wherein the transmission devices (285, 286) are arranged to transmit rotation movements from the actuation mechanism to the stator blades (221, 222) of said row, wherein the actuation mechanism is positioned between the outer casing and the inner casing; wherein the plurality of transmission devices comprises a plurality of actuation rods, wherein each of said stator blades has a spanwise direction, wherein each actuation rod is rigidly coupled to a respective stator blade and extends parallel to said spanwise direction, characterised in that each of the actuation rods of said plurality has an axial rod hole whereby a first rod end and a second rod end are fluidly connected, wherein each of the stator blades of said row has a vane hole whereby a first vane end and a second vane end are fluidly connected, and wherein said rod hole is fluidly connected with said vane hole. the plurality of transmission devices comprises a plurality of actuation rods, wherein each of said stator blades has a spanwise direction, wherein each actuation rod is rigidly coupled to a respective stator blade and extends parallel to said spanwise direction, characterised in that each of the actuation rods of said plurality has an axial rod hole whereby a first rod end and a second rod end are fluidly connected, wherein each of the stator blades of said row has a vane hole whereby a first vane end and a second vane end are fluidly connected, and wherein said rod hole is fluidly connected with said vane hole.