Section 4. The commission shall negotiate with and purchase, on such terms as it deems to be in the best interest of the commonwealth and its employees, from one or more insurance companies, savings banks or non-profit hospital or medical service corporations, a policy or policies of group life and accidental death and dismemberment insurance covering persons in the service of the commonwealth, and group general or blanket insurance providing hospital, surgical, medical, dental and other health insurance benefits covering persons in the service of the commonwealth and their dependents, and shall execute all agreements or contracts pertaining to said policies or any amendments thereto for and on behalf and in the name of the commonwealth. Said commission may negotiate a contract for such term not exceeding five years as it may, in its discretion, deem to be the most advantageous to the commonwealth; provided, however, that the portion of the cost of the premium per month to be borne by the commonwealth shall not exceed the estimated monthly cost for which funds have been appropriated by the general court for the then current fiscal year.

For the purposes of this chapter, any nonprofit hospital service corporation or nonprofit medical corporation organized under chapter one hundred seventy-six A or one hundred and seventy-six B shall be and is hereby authorized to enter into a reinsurance agreement as herein provided in the same manner as any other insurance company.