If the funds at the disposal or which may be obtained by the department of social services for the payment of public assistance money payment benefits or to or on behalf of any person for medical assistance benefits shall at any time become insufficient to pay the full amount thereof, the amount of any type of payment to or on behalf of each of such persons shall be reduced pro rata in proportion to such deficiency in the total amount available or to become available for such purpose.
§ 208.154, RSMo