(1) No person shall construct any building or put up any structure likely to affect the utility of the park, play-field or open space or make any encroachment in or over any park, play-field or open space specified in the list published under section 4 or section 5 :
Provided that the executive authority may, subject to such rules as may be prescribed, permit the construction of such buildings or putting up of such structures as may be necessary for the improvement or more beneficial utilisation of the park, play-field or open space.
(2) No land or building within a park, play-field or open space specified in the list published under section 4 or section 5 shall be alienated by way of sale, lease, gift, exchange, mortgage or otherwise and no licence for the use of any such land or buildings for any other purposes shall be granted and any alienation made or licence granted in contravention of this section shall be null and void.