A method is provided to control a hybrid powertrain to achieve gear shifts without torque interruption, comprising a gearbox with input shaft and output shafts; a first planetary gear connected to the input shaft and a first main shaft; a second planetary gear connected to the first planetary gear and a second main shaft; first and second electrical machines respectively connected to the first and second planetary gears; a first gear pair and a third gear pair between the first main shaft and a countershaft; and a second gear pair between the second main shaft and the countershaft, which is connected with the output shaft via a fifth gear pair. The method comprises disconnecting the first gear pair; connecting the first planetary gear with the output shaft via a coupling mechanism connecting the first main shaft and output shaft; disconnecting the fifth gear pair; transferring torque generated from the combustion engine from the second planetary gear to the countershaft via the second gear pair; and transferring a torque from the countershaft to the output shaft via the third gear pair.