The provisions of this article to the extent that they relate to the unemployment trust fund must be operative only so long as the Secretary of the Treasury of the United States continues to maintain for this State a separate book account of all funds deposited in the trust fund by this State for benefit purposes, together with this State’s proportionate share of the earnings of the unemployment trust fund, from which no other state is permitted to make withdrawals. If and when the unemployment trust fund ceases to exist or a separate book account is no longer maintained, all money, properties, or securities in the trust fund belonging to the unemployment compensation fund of this State must be transferred to the treasurer of the unemployment compensation fund, who shall hold, invest, transfer, sell, deposit, and release the money, properties, or securities in a manner approved by the department in accordance with the provisions of Chapters 27 through 41 of this title. This money must be invested only in readily marketable bonds or other interest bearing obligations of the United States or of this State or a political subdivision of this State and these investments at all times must be made so that all the assets of the fund always must be readily convertible into cash when needed for the payment of benefits. The treasurer shall dispose of securities or other properties belonging to the unemployment compensation fund only under the direction of the department in accordance with the purposes and provisions of Chapters 27 through 41 of this title.