(1) A policy of insurance shall be an approved policy of insurance for the purposes of this Act if, but only if, it complies with the following conditions:

(a) it is issued by a vehicle insurer to a person (in this Act referred to as the insured) named therein;

(b) the insurer by whom it is issued binds himself by it to insure the insured against all sums without limit which the insured or his personal representative shall become liable to pay to any person whether by way of damages or costs on account of injury to person or property caused by the negligent use, during the period (in this Act referred to as the period of cover) specified in that behalf in the policy, of a mechanically propelled vehicle to which the policy relates, by the insured or by any of such other persons (if any) as are mentioned or otherwise indicated in that behalf in the policy;

(c) the liability of the insurer under the policy is not subject to any condition, restriction, or limitation prescribed as not to be inserted in an approved policy of insurance;