(a) Any provision in a liability policy of insurance which provides that the insurer shall have the right to compromise or settle claims of third persons against the insured without the consent of the insured shall be deemed to create, as between the insurer and the insured, the relationship of an independent contractor so that the insured shall not be precluded from asserting a claim or cause of action against third persons, notwithstanding the settlement by the insurer of such claims of third persons, unless the insured shall previously have consented in writing to relinquish his claim or cause of action against third persons, provided in all cases where the insurer shall settle the claims of third persons against the insured without written consent that it shall be the duty of the insurer to inform the third persons in writing of the lack of consent of the insured and that the insured is not thereby precluded from the further assertion of claims against the third persons before taking from the third persons any release, covenant not to sue, or other settlement; and upon the failure of the insurer to give the notice to the third persons of the lack of consent of the insured, the release, covenant not to sue, or other settlement shall be of no effect, null, and void.

(b) If such third persons execute a release, covenant not to sue, or other instrument in settlement of their claims after such notice of the lack of consent of the insured, the same shall be deemed and construed as a bar to the further assertion by such third persons of such claims against all persons whomsoever; and such third persons shall not plead such release, covenant not to sue, or settlement in bar of any action or claim asserted by such insured.