An assembly of a blade portion for a grooving tool and an insert; the blade portion comprising: opposite first and second surfaces (4, 5), wherein a blade width is defined as a shortest distance between the first and second surfaces (4, 5); opposite third and fourth surfaces (8, 9); a fifth surface and an opposite blade portion end; wherein the blade width is constant or substantially constant from the fifth surface up to the blade portion end; an insert seat separating the third surface and the fifth surface; wherein the insert seat receives the insert comprising a main cutting edge, an associated rake face, and an associated main clearance surface; wherein the main cutting edge defines an insert width being greater than the blade width; wherein a shortest distance from the fifth surface to the opposite blade portion end is greater than a shortest distance from the third surface to the fourth surface; wherein the insert comprises a top surface and an opposite bottom surface, a front surface and an opposite rear surface, a first side surface and an opposite second side surface; wherein the top surface comprises the rake face; wherein the front surface comprises the main clearance surface; wherein the insert is mounted in the insert seat such that a portion of the bottom surface and a portion of the rear surface is in contact with the insert seat; wherein a second mid-plane of the blade portion is equidistantly or substantially equidistantly between the opposite third and fourth surfaces (8, 9); and wherein the top surface of the insert comprises chip forming or chip breaking means, preferably in the form of one or more protrusions and/or one or more depressions, characterized in that the insert is mounted in the insert seat such that the main clearance surface and the third surface are facing in the same direction or in substantially the same direction; and wherein a plane parallel to the second mid-plane intersects the top and bottom surfaces (26, 27) of the insert. opposite first and second surfaces (4, 5), wherein a blade width is defined as a shortest distance between the first and second surfaces (4, 5); opposite third and fourth surfaces (8, 9); a fifth surface and an opposite blade portion end; wherein the blade width is constant or substantially constant from the fifth surface up to the blade portion end; an insert seat separating the third surface and the fifth surface; wherein the insert seat receives the insert comprising a main cutting edge, an associated rake face, and an associated main clearance surface; wherein the main cutting edge defines an insert width being greater than the blade width; wherein a shortest distance from the fifth surface to the opposite blade portion end is greater than a shortest distance from the third surface to the fourth surface; wherein the insert comprises a top surface and an opposite bottom surface, a front surface and an opposite rear surface, a first side surface and an opposite second side surface; wherein the top surface comprises the rake face; wherein the front surface comprises the main clearance surface; wherein the insert is mounted in the insert seat such that a portion of the bottom surface and a portion of the rear surface is in contact with the insert seat; wherein a second mid-plane of the blade portion is equidistantly or substantially equidistantly between the opposite third and fourth surfaces (8, 9); and wherein the top surface of the insert comprises chip forming or chip breaking means, preferably in the form of one or more protrusions and/or one or more depressions, characterized in that the insert is mounted in the insert seat such that the main clearance surface and the third surface are facing in the same direction or in substantially the same direction; and wherein a plane parallel to the second mid-plane intersects the top and bottom surfaces (26, 27) of the insert.