A mast-climbing robot has first and load-bearing assemblies, at least one linear actuator connected between the assemblies for changing their vertical spacing, and a respective clamp on each load-bearing assembly that can secure the respective load-bearing assembly on the mast and release the respective load-bearing assembly therefrom. Each clamp has two bearing points on the respective load-bearing assembly, at least one flexible belt that extends between the two bearing or attachment points and circumferentially around the mast, and at least one clamping actuator with which the length of the at least one belt can be increased and decreased between the bearing or attachment points to tighten lock the respective belt about the mast and thereby lock the respective assembly on the mast.