Abstract: The closure assembly (1) comprises: a pourer unit (2) having a lower portion (3) for fixing to the mouth of the container and an upper pouring portion (4), a removable cap (6) provided with a resiliently deformable peripheral lip portion (7), and an outer covering (8, 9) including: an upper sleeve element (8) which closely surrounds the cap (6) leaving the lip portion (7) thereof substantially exposed, and a lower sleeve element (9) which is separate from the upper sleeve element (8) and closely surrounds the lower portion (3) of the pourer unit (2) and which, prior to the first opening of the closure assembly (1), extends at a predetermined distance (d) from the upper sleeve element (8) and at least partially surrounds the lip portion (7) of the cap (6).