65 ILCS 5/8-4-22

The corporate authorities of any such municipality are authorized to take any action that may be necessary to inform owners of outstanding securities regarding the financial condition of the fund out of which the securities are payable and the necessity of refunding the same and readjusting the maturities thereof and the corporate authorities may enter into any agreements required to prepare and carry out any refunding plan, and without previous appropriation therefor under any law may incur and pay expenditures that may be necessary in order to accomplish the refunding of such securities.