The disclosure relates to a medicament delivery device, comprising: a tubular body having a distal end, a cap adapted to be connected to the distal end (of the body, wherein the body comprises a first clip having a first stop and a first ramp, wherein the cap comprises a second clip having a second stop and a second ramp, wherein the first ramp and the second ramp are adapted to be mutually engaged when the cap is connected to the body in a first position, wherein the first ramp and the second ramp are adapted to resiliently deflect at least one of the first clip and the second clip when the cap is being moved from the first position towards a second position, wherein in the second position the first stop and the second stop abut each other to prevent the cap from being moved into the first position. Furthermore, the disclosure relates to a method for assembling the medicament delivery device.