Section 34Q. Notwithstanding any general or special law, regulation or rule to the contrary, there is hereby authorized the insurance of liabilities incurred in the operation of motor vehicles by nonowner operators or in the operation of hired motor vehicles by endorsements in a general liability policy of insurance or by endorsements in a multi-peril policy of insurance, such endorsements to be distinct from, or in addition to, such endorsements presently authorized in statutory motor vehicle policies of insurance.