Upon compliance with the provisions of this act, an alien insurer now or hereafter licensed to do business in this State which owns beneficially, directly or indirectly, all of the outstanding capital stock (other than directors' qualifying shares) of any domestic insurer incorporated for the purpose of transacting the same or similar classes of insurance which the United States branch of the alien insurer is qualified and licensed to transact, may, with the prior written approval of the Insurance Commissioner and of the insurance supervisory official of the regulatory State of the United States branch of the alien insurer and subject to the final approval of the Insurance Commissioner and of the aforesaid supervisory official, domesticate its United States branch by entering into an agreement in writing with the domestic insurer providing for the acquisition by the domestic insurer of the business and assets of the United States branch of the alien insurer and the assumption by the domestic insurer of all of the liabilities of the United States branch for no consideration other than the assumption of such liabilities except the agreement may further provide for additional consideration payable by the issuance by the domestic insurer of shares of its capital stock. For the purposes of this act, those shares of capital stock of the domestic insurer or voting trust certificates representing said shares, as are held among the trusteed assets of the United States branch of the alien insurer or are held in a trust created by the alien insurer and of which the alien insurer is a beneficiary shall be deemed to be shares held beneficially, but indirectly, by an alien insurer. The acquisition of assets and assumption of liabilities of the United States branch by the domestic insurer shall be affected by the filing of an instrument of transfer and assumption with the insurance supervisory official of the regulatory state which instrument shall be in form satisfactory to the Insurance Commissioner and the aforesaid supervisory official and shall be executed by the alien insurer and the domestic insurer.