A cutting tool comprising an insert holder and an indexable cutting insert removably secured therein, the insert holder comprising: a holder head and a holder shank extending rearwardly therefrom along a holder axis, the holder head having spaced apart lower and upper clamping portions (30, 32) located on opposite sides of a first plane containing the holder axis, the lower clamping portion extending along a pivot axis, and the upper clamping portion displaceable relative to the lower clamping portion and having an upper clamping surface which is intersected by a second plane perpendicular to the first plane, the cutting insert comprising: opposing first and second end surfaces (40, 42) with a peripheral surface extending therebetween and an insert axis extending therethrough, the peripheral surface having a plurality of cutting portions circumferentially spaced apart about the insert axis, the plurality of cutting portions including an operative first cutting portion having an operative first cutting edge formed at the intersection of a first rake surface and a first relief surface, the first rake surface facing in a first direction about the insert axis, wherein: the upper clamping surface makes contact with a first abutment portion of the peripheral surface, a second abutment portion (56") of the peripheral surface makes contact with the lower clamping portion, and the second plane intersects the plurality of cutting portions, the cutting tool being characterised by having spaced apart first and second lower clamping surfaces (34, 36) located on opposite sides of the second plane, wherein the second abutment portion (56") of the peripheral surface makes contact with the first and second lower clamping surfaces (34, 36), wherein the first and second lower clamping surfaces (34, 36) are entirely located on opposite sides of a third plane parallel to the second plane, and wherein the third plane does not intersect the upper clamping surface. the insert holder comprising: a holder head and a holder shank extending rearwardly therefrom along a holder axis, the holder head having spaced apart lower and upper clamping portions (30, 32) located on opposite sides of a first plane containing the holder axis, the lower clamping portion extending along a pivot axis, and the upper clamping portion displaceable relative to the lower clamping portion and having an upper clamping surface which is intersected by a second plane perpendicular to the first plane, the holder head having spaced apart lower and upper clamping portions (30, 32) located on opposite sides of a first plane containing the holder axis, the lower clamping portion extending along a pivot axis, and the upper clamping portion displaceable relative to the lower clamping portion and having an upper clamping surface which is intersected by a second plane perpendicular to the first plane, the cutting insert comprising: opposing first and second end surfaces (40, 42) with a peripheral surface extending therebetween and an insert axis extending therethrough, the peripheral surface having a plurality of cutting portions circumferentially spaced apart about the insert axis, the plurality of cutting portions including an operative first cutting portion having an operative first cutting edge formed at the intersection of a first rake surface and a first relief surface, the first rake surface facing in a first direction about the insert axis, wherein: the upper clamping surface makes contact with a first abutment portion of the peripheral surface, a second abutment portion (56") of the peripheral surface makes contact with the lower clamping portion, and the second plane intersects the plurality of cutting portions, the cutting tool being characterised by having spaced apart first and second lower clamping surfaces (34, 36) located on opposite sides of the second plane, wherein the second abutment portion (56") of the peripheral surface makes contact with the first and second lower clamping surfaces (34, 36), wherein the first and second lower clamping surfaces (34, 36) are entirely located on opposite sides of a third plane parallel to the second plane, and wherein the third plane does not intersect the upper clamping surface. the upper clamping surface makes contact with a first abutment portion of the peripheral surface, a second abutment portion (56") of the peripheral surface makes contact with the lower clamping portion, and the second plane intersects the plurality of cutting portions, the cutting tool being characterised by having spaced apart first and second lower clamping surfaces (34, 36) located on opposite sides of the second plane, wherein the second abutment portion (56") of the peripheral surface makes contact with the first and second lower clamping surfaces (34, 36), wherein the first and second lower clamping surfaces (34, 36) are entirely located on opposite sides of a third plane parallel to the second plane, and wherein the third plane does not intersect the upper clamping surface.