Exhibit 4.14



================================================================================





                        FIRST AMENDMENT TO LOAN AGREEMENT



                          Dated as of February 1, 2004

                                     Between

         STATE ENVIRONMENTAL IMPROVEMENT AND ENERGY RESOURCES AUTHORITY



                                       and



                      UNION ELECTRIC COMPANY, DBA AMERENUE
                  ---------------------------------------------
                     Supplementing and amending that certain
                                 Loan Agreement
                            dated as of March 1, 2000


                                  $186,500,000
         State Environmental Improvement and Energy Resources Authority
                Environmental Improvement Revenue Refunding Bonds
                        (Union Electric Company Project)
                            $63,500,000 Series 2000A
                            $63,000,000 Series 2000B
                                       and
                            $60,000,000 Series 2000C
                  ---------------------------------------------






================================================================================


<PAGE>



                        FIRST AMENDMENT TO LOAN AGREEMENT
                            ------------------------


                                TABLE OF CONTENTS

 (This Table of Contents is not a part of the First Amendment to Loan Agreement
                   and is only for convenience of reference.)

<TABLE>
<CAPTION>

SECTION                                                HEADING                                                   PAGE
<S>     <C>               <C>
ARTICLE I                  DEFINITIONS............................................................................2

       Section 1.01.       Definitions of Terms...................................................................2

ARTICLE II                 AMENDMENTS TO ORIGINAL AGREEMENT.......................................................2

       Section 2.01.       Amendments to Article IV of the Original Agreement.....................................2
       Section 4.07.       Credit Facility........................................................................2
       Section 2.02.       Amendment to Section 5.01 of the Original Agreement....................................6
       Section 2.03.       Amendment to Article VII of the Original Agreement.....................................6
       Section 2.04        Amendment to Section 8.01 of the Original Agreement....................................6

ARTICLE III                MISCELLANEOUS..........................................................................7

       Section 3.01.       Agreement Confirmed....................................................................7
       Section 3.02.       Severability...........................................................................7
       Section 3.03.       Counterparts...........................................................................7
       Section 3.04.       Applicable Provisions of Law...........................................................7
       Section 3.05.       Effective Date.........................................................................7

</TABLE>

                                       i



<PAGE>

                        FIRST AMENDMENT TO LOAN AGREEMENT

     THIS FIRST AMENDMENT TO LOAN AGREEMENT (this "First Amendment") is made and
entered into as of February 1, 2004 between the STATE ENVIRONMENTAL  IMPROVEMENT
AND ENERGY  RESOURCES  AUTHORITY of the State of Missouri,  a body corporate and
politic  and a  governmental  instrumentality  of the  State  of  Missouri  (the
"Issuer"),  and UNION ELECTRIC COMPANY, a Missouri corporation doing business as
AMERENUE (the "Company"):


                                   WITNESSETH:

     WHEREAS,  on March 9, 2000 the Issuer issued its Environmental  Improvement
Revenue Refunding Bonds (AmerenUE Project) Series 2000A, Series 2003B and Series
2003C (the "Bonds") in the original  aggregate  principal amount of $186,500,000
pursuant  to a  Trust  Indenture  dated  as of  March  1,  2000  (the  "Original
Indenture") by and between the Issuer and UMB Bank & Trust,  N.A.,  successor to
State Street Bank and Trust Company of Missouri, N.A. (the "Trustee"); and

     WHEREAS,  in connection with the issuance of the Bonds,  the Issuer and the
Company  executed and delivered the Loan Agreement  dated as of March 1, 2000 by
and between the Issuer and the Company (the "Original Agreement"); and

     WHEREAS,  the  Original  Indenture  is being  amended  and  restated by the
Amended and Restated Trust Indenture of even date herewith (the  "Indenture") in
connection with a Change of Credit Facility,  i.e., to secure the Bonds with the
Bond Insurance Policy and the Company's First Mortgage Bonds;

     WHEREAS,  Section  12.05(j) of the  Original  Indenture  provides  that the
Issuer and the Company may,  without notice to or the consent of any Bondholder,
enter into an agreement  supplemental to the Original  Agreement to make changes
in connection with a Change of Credit Facility, and Section 9.04 of the Original
Agreement  provides that such  supplemental  agreement is subject to the written
consent of the Trustee; and

     WHEREAS,  the  Issuer  and the  Company  desire to enter  into  this  First
Amendment,  as  permitted  by Section  12.05(j) of the  Original  Indenture  and
Section 9.04 of the Original Agreement, in order to amend the Original Agreement
in connection with a Change of Credit Facility;

     NOW,  THEREFORE,  in  consideration  of the  foregoing  and  of the  mutual
covenants herein set forth, the parties hereto agree as follows:

<PAGE>


                                    ARTICLE I

                                   DEFINITIONS

        Section 1.01. Definitions of Terms. For all purposes of this First
Amendment, in addition to the terms defined above in the WHEREAS clauses, unless
the context clearly requires otherwise, all terms defined in Article I of the
Indenture have the same meanings in this First Amendment.


                                   ARTICLE II

                        AMENDMENTS TO ORIGINAL AGREEMENT

     Section 2.01. Amendments to Article IV of the Original Agreement. (a) There
is hereby added a new  paragraph  (c) to the end of Section 4.01 of the Original
Agreement to read as follows:

               "(c) The  Company  agrees  to make all  payments  when due on the
               First  Mortgage  Bonds.  If for any  reason  amounts  paid to the
               Trustee on the First Mortgage  Bonds,  together with other moneys
               held by the Trustee and available for that purpose,  would not be
               sufficient  to make the  corresponding  payments of principal of,
               premium,  if any, and interest on the Bonds corresponding to such
               First Mortgage  Bonds when such payments  become due, the Company
               will pay the  amounts  required  from time to time to make up any
               such deficiency."

     (b)  Section  4.07 of the Original  Agreement is hereby  amended to read as
follows:

                    "Section 4.07. Credit Facility. (a) On the Issue Date, there
               was no Credit Facility. The Company may at any time provide for a
               Change of Credit Facility,  provided that the Company delivers to
               the Trustee,  the Auction Agent and the  Remarketing  Agent,  not
               less  than  five  Business  Days  prior to the date on which  the
               Trustee  must notify the Owners of the  applicable  series of the
               Bonds of a Change of Credit Facility  pursuant to Section 2.18 of
               the Indenture and prior to the effective  date of any such Change
               of Credit Facility, the following:

                    (1)  a notice  which (A)  states the  effective  date of the
                         Change of Credit  Facility,  (B) describes the terms of
                         the  Change of Credit  Facility,  and (C)  directs  the
                         Trustee to give notice  pursuant to Section  2.18(a) of
                         the Indenture;

                                      -2-

<PAGE>

                    (2)  a Favorable  Opinion of Bond  Counsel  with  respect to
                         such Change of Credit Facility and stating,  in effect,
                         that such change of Credit Facility is authorized under
                         this Agreement;

                    (3)  a certificate of an Authorized  Company  Representative
                         as to whether the  applicable  series of Bonds are then
                         rated by either Moody's or S&P, or both; and

                    (4)  written  evidence from Moody's,  if such Bonds are then
                         rated by Moody's,  and from S&P, if such Bonds are then
                         rated by S&P,  in each  case to the  effect  that  such
                         rating  agency  has  reviewed  the  proposed  Change of
                         Credit Facility and that such Change of Credit Facility
                         will not, by itself, result in a reduction,  suspension
                         or withdrawal of its rating or ratings of such Bonds.

               (b)  In lieu of satisfying  the  requirements  of subsection  (a)
          above,  the Company may provide for a Change of Credit Facility at any
          time  that the  applicable  series of Bonds are  subject  to  optional
          redemption pursuant to Section 4.02(b) of the Indenture, provided that
          the  Company  delivers  to the  Trustee,  the  Auction  Agent  and the
          Remarketing  Agent not less than 30 days before the effective  date of
          the Change of Credit Facility:

                    (1)  a notice  which (A)  states the  effective  date of the
                         Change of Credit  Facility,  (B) describes the terms of
                         the Change of Credit Facility,  (C) directs the Trustee
                         to  give  notice   pursuant  to  Section  2.18  of  the
                         Indenture that the Bonds of the  applicable  series are
                         subject to mandatory  purchase,  in whole, on or before
                         the effective date of the Change of Credit  Facility in
                         accordance with Section  3.02(a)(iii) of the Indenture,
                         and (D) directs the Trustee to take any other action as
                         shall be  necessary  for the  Trustee to take to effect
                         the Change of the Credit Facility; and

                    (2)  on or before the effective date of the Change of Credit
                         Facility,  the Company  shall  furnish to the Trustee a
                         Favorable  Opinion  of  Bond  Counsel   satisfying  the
                         requirements of Section 4.07(a)(2) above.

               (c)  The  Company may  provide  for one or more  extensions  of a
          Credit  Facility  for any  period  commencing  after its  then-current
          expiration  date without  complying  with the foregoing  provisions of
          this Section.

                                      -3-

<PAGE>

               (d)  The Company  may  rescind  its  election to make a Change of
          Credit Facility at any time prior to the effective date thereof."

         (c) Section 4.09, Section 4.10 and Section 4.11 are hereby added to the
end of Article IV of the Original Agreement to read as follows:

                    "Section  4.09.  First  Mortgage  Bonds.  The Company  shall
               execute  and deliver to the  Trustee,  as assignee of the Issuer,
               its First  Mortgage  Bonds.  The form of the First Mortgage Bonds
               will be substantially as set forth in the Company's  Supplemental
               Indenture to its Mortgage  executed and  delivered to the Trustee
               on the effective date of this First Amendment."

                    "Section  4.10.  Payment of the Bonds from  Payments  of the
               First Mortgage Bonds and Other Amounts. Payments of principal of,
               and premium, if any, and interest on, the First Mortgage Bonds by
               the Company to the  Trustee,  as  assignee  of the Issuer,  shall
               constitute  payments  of such  amounts on the loan under  Section
               4.01(a).  Each series of the Bonds shall be payable from payments
               made by the Company to the Trustee of  principal  and interest on
               the  corresponding  series  of  First  Mortgage  Bonds  delivered
               hereunder.  Payments  of  principal  of or  premium,  if any,  or
               interest  on, each series of the Bonds with moneys held under the
               Indenture  for such payment  shall be deemed to be like  payments
               with respect to the corresponding series of First Mortgage Bonds.
               The  obligations  of the Company to make payments under the First
               Mortgage  Bonds shall be absolute and  unconditional.  Whenever a
               series of the Bonds is redeemable in whole or in part, the Issuer
               will  redeem the same upon the  request of the  Company,  and the
               Company  covenants  and  agrees  to pay an  amount  equal  to the
               applicable  redemption  price of such  Bonds as a  prepayment  of
               principal of and interest due on the  applicable  series of First
               Mortgage  Bonds.  If the Company  prepays any series of the First
               Mortgage Bonds, the Company's obligations under Section 4.01 will
               be satisfied and there will be a corresponding  redemption of the
               applicable  series  of  Bonds.   Whenever  payment  or  provision
               therefor has been made in respect of the principal of or interest
               on all or any  portion of any  series of the Bonds in  accordance
               with the  Indenture  (whether at maturity or upon  redemption  or
               acceleration),  the  applicable  series of First  Mortgage  Bonds
               shall be deemed  paid to the extent  such  payment  or  provision
               therefor  has been  made and is  considered  to be a  payment  of
               principal or interest on the Bonds. If any series of the Bonds or
               any  portion  thereof  are  thereby  deemed  paid in full,  First
               Mortgage  Bonds of the  applicable  series in a principal  amount
               equal to the principal

                                      -4-

<PAGE>

               amount of such Bonds so deemed to be paid shall be cancelled  and
               returned to the Company.  Subject to the  foregoing or unless the
               Company  is  entitled  to a credit  under this  Agreement  or the
               Indenture,  all  payments  shall be in the full  amount  required
               under the First Mortgage Bonds.

                    If the Company has deposited  moneys and/or U.S.  Government
               Obligations  and  obtained  the  release  of a  series  of  First
               Mortgage  Bonds  pursuant to Section 8.01 and Section 8.02 of the
               Indenture,  and  thereafter  the  corresponding  series  of Bonds
               become subject to mandatory  redemption upon a  determination  of
               taxability and there are insufficient  moneys available under the
               Indenture to effect such  redemption,  the Company  covenants and
               agrees  to  pay to the  Trustee  under  the  Indenture  any  such
               deficiency  amount as is  necessary  to redeem  such Bonds on the
               date fixed for redemption.

                    The Issuer, by the terms of the Indenture, shall require the
               Trustee to notify in writing the Mortgage Trustee of all payments
               or credits with respect to the First Mortgage Bonds."

                    "Section  4.11.  Assignment  of  Issuer's  Rights  to  First
               Mortgage  Bonds.  As security  for the payment of its Bonds,  the
               Issuer  hereby  pledges  and  assigns  to the  Trustee  the First
               Mortgage Bonds and the right to receive payments thereunder.  The
               Issuer directs the Company, and the Company agrees, to pay to the
               Trustee at its principal  corporate  trust office all payments on
               the First Mortgage  Bonds,  and other payments due and payable to
               the Trustee hereunder. The Company will make payments directly to
               the Trustee  without  defense or set-off by reason of any dispute
               between the  Company  and the  Trustee or the Issuer.  The Issuer
               hereby  agrees that the  Trustee as assignee  may enforce any and
               all rights and remedies hereunder,  but retains the right to also
               proceed in its own name  against the Company for the  enforcement
               of the  specific  performance  of any  obligation  of the Company
               under Sections 4.04,  4.06(a),  5.03,  5.06, 5.07, 5.08 and 7.05;
               provided,  that in any such action seeking specific  performance,
               the  Issuer  shall  have no  rights  with  respect  to the  First
               Mortgage Bonds and in such event the obligation of the Company to
               make the  payments  required  to repay  the  loan  hereunder  and
               payments  required  under the First  Mortgage  Bonds shall remain
               unconditional as provided in Section 4.01.

                    The Issuer and the Company covenant and agree that the First
               Mortgage Bonds will at all times be (i) in fully registered (both
               principal and interest)  form; (ii) registered in the name of the

                                      -5-

<PAGE>

               Trustee;  (iii)  non-transferable   except  as  provided  in  the
               Mortgage;  and (iv) appropriately  marked to indicate clearly the
               restrictions on the transfer thereof imposed by this Agreement."

     Section 2.02.  Amendment to Section 5.01 of the Original Agreement.  Clause
(I) Subsection (ii) of Section 5.01 of the Original  Agreement is hereby amended
to read as follows:

               "(I) such entity is qualified to do business in the State and has
               assumed in writing all of the  obligations  of the Company  under
               this  Agreement,  the Tax  Agreement,  the Mortgage and the First
               Mortgage Bonds and"

     Section  2.03.  Amendment  to Article VII of the  Original  Agreement.  (a)
Section  7.01(b) of the Original  Agreement is hereby  amended by the  following
proviso, to be added at the end of Section 7.01(b):

               "; and  further  provided,  however,  that  failure  pursuant  to
               Section  4.10 shall be an  automatic  Event of  Default  upon the
               expiration of any grace period  applicable to the First  Mortgage
               Bonds under the Mortgage."

     (b)  There is hereby added a new Section 7.01(e) at the end of Section 7.01
to read as follows:

               "(e) the  occurrence  of an  acceleration  for any  reason of the
               maturity of all first mortgage bonds issued under the Mortgage."

     (c)  The following  phrase is hereby added to the end of Section 7.03(a) of
the Original Agreement as follows:

               "and the Trustee may take whatever action may appear necessary or
               desirable to collect the  payments  then due and to become due or
               to enforce performance of the First Mortgage Bonds."

     Section  2.04.  Amendment to Section 8.01 of the  Original  Agreement.  The
first  sentence of Section 8.01 of the Original  Agreement is hereby  amended to
include the following phrase at the end of such sentence:

               ", and that a  corresponding  prepayment has been made or will be
               made, by redemption or otherwise, of the First Mortgage Bonds."

                                      -6-

<PAGE>


                                   ARTICLE III

                                  MISCELLANEOUS

     Section  3.01.  Agreement  Confirmed.  Except  as  amended  by  this  First
Amendment,  all of the provisions of the Original Agreement shall remain in full
force and effect,  and from and after the effective date of this First Amendment
shall be deemed to have been amended as herein set forth.

     Section 3.02. Severability.  If any provision of this First Amendment shall
be held or deemed to be or shall,  in fact, be inoperative or  unenforceable  as
applied in any particular case in any  jurisdiction or  jurisdictions  or in all
jurisdictions,  or in all cases because it conflicts with any other provision or
provisions  hereof or any  constitution or statute or rule of public policy,  or
for any other reason,  such circumstances shall not have the effect of rendering
the  provision in question  inoperative  or  unenforceable  in any other case or
circumstance, or of rendering any other provision or provisions herein contained
invalid, inoperative, or unenforceable to any extent whatever.

     Section 3.03.  Counterparts.  This First  Amendment  may be  simultaneously
executed in several counterparts,  each of which shall be an original and all of
which shall constitute but one and the same instrument.

     Section 3.04.  Applicable  Provisions of Law. This First Amendment shall be
governed by and construed in accordance with the laws of the State of Missouri.

     Section 3.05.  Effective Date. This First Amendment shall become  effective
on the date the Trustee has received the consent of the Trustee to the execution
hereof.

                                      -7-

<PAGE>


     IN WITNESS  WHEREOF,  the Issuer and the  Company  have  caused  this First
Amendment to be executed in their respective corporate names, and the Issuer has
caused its seal to be  hereunto  affixed  and  attested  by its duly  authorized
officer, all as of the date first above written.

                                           STATE ENVIRONMENTAL IMPROVEMENT AND
                                             ENERGY RESOURCES AUTHORITY



                                           By:  /s/ Charles D. Banks
                                              ----------------------------------
                                                         Chairman

[SEAL]

ATTEST:


By:  /s/ Deron L. Cherry
   ---------------------------------
               Secretary

                                           UNION ELECTRIC COMPANY, DBA AMERENUE



                                           By:  /s/ Jerre E. Birdsong
                                              ----------------------------------
                                           Title:  Vice President and Treasurer




                                      -8-

<PAGE>





                             CONSENT OF THE TRUSTEE

     Pursuant  to  Section  10.4  of  the  Loan  Agreement   between  the  State
Environmental  Improvement  and  Energy  Resources  Authority  of the  State  of
Missouri (the "Issuer") and Union Electric Company dba AmerenUE (the "Company"),
dated as of March 1, 2000,  UMB Bank & Trust,  N.A.,  successor  to State Street
Bank and Trust  Company of Missouri,  N.A., as Trustee,  hereby  consents to the
execution  and  delivery of the First  Amendment to Loan  Agreement  dated as of
February 1, 2004 between the Issuer and the Company.

                                   UMB BANK & TRUST, N.A., successor to State
                                     Street Bank and Trust Company of Missouri,
                                     N.A.



                                   By:  /s/ R.A. Dengler
                                      ------------------------------------------
                                      Its  Authorized Officer

Date:  March 17, 2004