EXHIBIT F


                       (Letterhead of Steven R. Sullivan)



                                            June 3, 2002


Securities and Exchange Commission
450 Fifth Street, NW
Washington, DC  20549


         RE:   AMEREN CORPORATION - APPLICATION/DECLARATION ON FORM U-1
               (FILE NO. 70-9965)

Dear Sirs:

         I refer to the Form U-1 Application/Declaration (the "Application")
under the Public Utility Holding Company Act of 1935 (the "Act"), filed with the
Securities and Exchange Commission (the "Commission") by Ameren Corporation
("Ameren"), a registered holding company, and certain of its non-utility
subsidiaries. In the Application, Ameren has requested authorization to invest,
indirectly through its non-utility subsidiaries, up to $125 million from time to
time through December 31, 2005, in the passive securities of one or more
entities owning existing or new low income housing tax credit projects or
historic building or other qualified rehabilitated building projects
(collectively, "Tax Credit Projects"). I have acted as counsel for the
applicants in connection with the Application.

         In connection with the opinions given herein, I have examined original,
certified, or conformed copies of all such corporate records, agreements,
instruments, and documents and have made such other investigations as I have
deemed necessary or appropriate for the purpose of rendering the opinions given
herein. In my examination, I have assumed the genuineness of all signatures, the
authenticity of all documents submitted to me as originals and the conformity to
originals of all documents submitted to me as conformed copies. In giving the
opinions below, I have assumed that the Commission will issue an order granting
the request made in the Application.

         Based on the foregoing, and having regard to legal considerations which
I deem relevant, I am of the opinion that:

         1. All state laws applicable to the acquisition and continued ownership
of passive interests in Tax Credit Projects will have been complied with;





Securities and Exchange Commission
June 3, 2002
Page 2


         2.  Ameren will legally acquire, indirectly through its non-utility
subsidiaries, passive interests in Tax Credit Projects, as described in the
Application; and

         3.  The proposed transactions will not violate the legal rights of the
holders of any securities issued by Ameren or any of its associate companies.

         The opinions expressed herein are limited to the laws of the State of
Missouri. To the extent that any of the opinions expressed herein is based upon
the laws of another State, I will obtain and rely upon opinions of other counsel
qualified to practice in such jurisdictions, in form satisfactory to me, as I
may deem appropriate. I hereby consent to the use of this opinion in connection
with the Application. This opinion is intended solely for the use of the
Commission and may not be relied upon by any other person.


                                       Sincerely,



                                       /s/ Steven R. Sullivan
                                       ------------------------------
                                       Vice President, General Counsel and
                                              Secretary