Embodiments provide a urinary catheter assembly comprising an outer package of gas- impermeable material and an intermittent urinary catheter arranged inside the outer package. The catheter comprises a proximal insertion end, a distal connection end, and a connector at the distal end. The connector defines a distal opening. The catheter assembly further comprises a sleeve of liquid-impermeable material configured to define at least part of a liquid tight enclosure. The enclosure encloses the insertable part of the catheter. The enclosure is closed by a first closure in the proximal end and a second closure in the distal end. The second closure is configured to be opened as the outer package is opened and the first closure is configured to be opened as the catheter and sleeve is removed from the outer package.