An internal milling cutter includes a carrier disk having a centre axis defining an axis of rotation of the milling cutter, a plurality of separated tool holder segments removably mounted at the inner circumference of the carrier disk, and at least one clamp for each tool holder segment mounted either on the carrier disk or on the tool holder segment. Each of the tool holder segments at its inner circumference includes at least one cutting insert seat with a mounting element for a cutting insert or at least one cutting edge. The clamp is located and arranged such that it generates a force in the axial direction pressing the axial contact surface of the tool holder segment onto the axial abutment surface of the carrier disk, and the clamp is mounted movably in a radial direction of the carrier disk between a locking position and a releasing position.