6. Restriction on the holding of driving licences.

(1) No person shall come while he holds any driving licence for the time being in force, hold any other driving licence except a learner's licence or a driving licence issued in accccordance with the provisions of section 18 or a document authorising, in accccordance with the rules made under section 139, the person specified therein to drive a motor vehicle.

(2) No holder of a driving licence or a learner's licence shall permit it to the used by any other person.

(3) Nothing in this section shall prevent a licensing authority having the jurisdiction referred to in sub-section (1) of section 9 from adding to the classes of vehicles which the driving licence authorises the holder to drive.