The city council of a city of the primary class may enter into an agreement with a corporation or association organized for charitable purposes in such city for the erection and management of a hospital for the sick and disabled and have a permanent interest therein to an extent and upon such terms and conditions as may be agreed upon between the city council and such corporation or association. The city council shall provide for the payment of the amount agreed upon, for any interests in such hospital, either in one payment or in installments, or so much from year to year as the parties may stipulate. Such agreement shall not be made if the city shall have established a hospital as authorized by section 15-231. No such agreement shall extend more than one year.