An apparatus comprising a gripper frame, connected with an arm or beam for displacing the gripper frame, two gripper blades which are rotatably connected with the gripper frame, two supporting strips each connected along hinges extending substantially in horizontal direction with each respective one of the two supporting strips, a driver which performs a vertical movement for engaging such packaging units in an engagement position and releasing such packaging units in a release position, and a controller connected with the gripper frame, the supporting strips, and the driver. The controller comprise a single lift plate arranged under the gripper frame and between the gripper blades. A vertical upward movement of the lift plate moves the supporting strips to an engagement position to clamp the packaging units between the gripper blades and downward movement of the lift plate moves the supporting strips to a release position.