News Releases

ST. LOUIS, Aug. 20, 2012 /PRNewswire/ -- Union Electric Company, doing business as Ameren Missouri ("Ameren Missouri"), a wholly owned subsidiary of Ameren Corporation (NYSE: AEE), announced today that it will seek to reduce the weighted average interest rate and enhance the maturity profile of its debt through the combination of a tender offer for four series of outstanding senior secured notes and a proposed public offering of its senior secured debt securities.

Ameren Missouri has commenced a tender offer to purchase for cash its outstanding 6.00% Senior Secured Notes due 2018 (the "6.00% Notes"), 6.70% Senior Secured Notes due 2019 (the "6.70% Notes"), 5.10% Senior Secured Notes due 2018 (the "2018 5.10% Notes"), and 5.10% Senior Secured Notes due 2019 (the "2019 5.10% Notes," and collectively with the 6.00% Notes, the 6.70% Notes and the 2018 5.10% Notes, the "Notes") for an aggregate purchase price (including principal and premium) of up to $377 million (the "Maximum Tender Amount").

The tender offer is being made upon and is subject to the terms and conditions set forth in the Offer to Purchase, dated August 20, 2012 (the "Offer to Purchase"), and the related Letter of Transmittal.

The tender offer will expire at midnight, New York City time, on September 19, 2012, unless extended or earlier terminated (the "Expiration Date").

Subject to the terms and conditions set forth in the Offer to Purchase, holders of Notes that are validly tendered and not withdrawn at or prior to 5:00 p.m., New York City time, on September 5, 2012 (the "Early Tender Date") and accepted for purchase will receive the applicable Total Consideration (as defined in the Offer to Purchase) which includes the early tender premium (the "Early Tender Premium") set forth in the table below. Holders of Notes that are validly tendered after the Early Tender Date but at or prior to the Expiration Date will receive the applicable Tender Offer Consideration (as defined in the Offer to Purchase), which is an amount equal to the Total Consideration minus the Early Tender Premium. The Total Consideration and the Tender Offer Consideration will be determined at 2:00 p.m., New York City time, on September 6, 2012 (unless such time is extended by Ameren Missouri).

The amount of each series of Notes that will be purchased in the tender offer will be based on the Maximum Tender Amount and the order of priority for such series of Notes set forth in the table below (the "Acceptance Priority Level"), as more fully described in the Offer to Purchase. Notes having a higher Acceptance Priority Level (with "1" being the highest) that are validly tendered and not validly withdrawn in the tender offer will be accepted for purchase up to the Maximum Tender Amount before any validly tendered and not validly withdrawn Notes having a lower Acceptance Priority Level are accepted for purchase, up to the Maximum Tender Amount for all Notes in the aggregate. Ameren Missouri reserves the right, in its sole discretion and subject to applicable law, to increase or decrease the Maximum Tender Amount.

The following table sets forth some of the principal terms of the tender offer:

Ameren Missouri intends to conduct an underwritten public offering of its senior secured debt securities under its effective shelf registration statement, to be completed prior to the Expiration Date (the "Debt Offering"), and to use a portion of the net proceeds from the Debt Offering, together with available cash, to fund the purchase of the Notes accepted in the tender offer and to pay all related fees and expenses.

Ameren Missouri's obligation to accept for payment and to pay for the Notes in the tender offer is subject to the satisfaction or waiver of a number of general conditions described in the Offer to Purchase and to the successful completion of the Debt Offering. Ameren Missouri has not yet entered into a definitive agreement with respect to the Debt Offering, and no assurance can be given that the Debt Offering will be completed.

Ameren Missouri will pay accrued and unpaid interest from and including the last interest payment date applicable to the relevant series of Notes up to, but not including, the settlement date for such Notes accepted for purchase. The settlement date is expected to be one business day following the Expiration Date, currently expected to be September 20, 2012.

Tenders of Notes may be withdrawn at any time at or prior to 5:00 p.m., New York City time, on September 5, 2012, but may not be withdrawn thereafter unless required by applicable law.

Barclays Capital Inc. is acting as the dealer manager for the tender offer. The depositary and information agent is Global Bondholder Services Corporation. Copies of the Offer to Purchase, the Letter of Transmittal and related offering materials are available by contacting Global Bondholder Services Corporation at 866.795.2200 (toll-free) or 212.430.3774 (collect). Questions regarding the tender offer should be directed to Barclays Capital Inc., Liability Management Group, at 800.438.3242 (toll-free) or 212.528.7581 (collect).

This news release shall not constitute an offer to sell, a solicitation to buy or an offer to purchase or sell any securities. The tender offer is being made only pursuant to the Offer to Purchase and only in such jurisdictions as is permitted under applicable law. The proposed Debt Offering will be made only by means of a prospectus and related prospectus supplement, which will be filed with the Securities and Exchange Commission. When available, copies of the prospectus supplement and accompanying prospectus for the offering may be obtained by contacting Ameren Corporation Investor Services toll-free at 800.255.2237.

About Ameren Missouri
Ameren Missouri delivers energy to 1.2 million electric and 127,000 natural gas customers in central and eastern Missouri, and its mission is to meet their energy needs in a safe, reliable, efficient and environmentally responsible manner. Ameren Missouri's service area covers 63 counties and 500 towns, including the greater St. Louis area. For more information, visit AmerenMissouri.com.

Forward-looking Statements
Statements made in this release which are not based on historical facts are considered "forward-looking" and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such "forward-looking" statements have been made in good faith and are based on reasonable assumptions, there is no assurance that the expected results will be achieved. These statements include, without limitation, statements as to future expectations, beliefs, plans, strategies, objectives, events, conditions, and financial performance. Ameren Missouri is providing this cautionary statement to identify important factors that could cause actual results to differ materially from those anticipated. The following factors, in addition to those discussed under Risk Factors in Ameren Missouri's Annual Report on Form 10-K for the year ended December 31, 2011, and elsewhere in this release and in its other filings with the SEC, could cause actual results to differ materially from management expectations suggested in such "forward-looking" statements:

• regulatory, judicial, or legislative actions, including changes in regulatory policies and ratemaking determinations, such as the outcome of Ameren Missouri's electric rate case filed in 2012; Ameren Missouri's fuel adjustment clause prudence review and the related request for an accounting authority order; and future regulatory, judicial, or legislative actions that seek to change regulatory recovery mechanisms;
• changes in laws and other governmental actions, including monetary, fiscal, and tax policies;
• changes in laws or regulations that adversely affect the ability of electric distribution companies and other purchasers of wholesale electricity to pay their suppliers, including Ameren Missouri;
• the effects of increased competition in the future due to, among other things, deregulation of certain aspects of Ameren Missouri's business at both the state and federal levels, and the implementation of deregulation;
• the effects on demand for Ameren Missouri's services resulting from technological advances, including advances in energy efficiency and distributed generation sources, which generate electricity at the site of consumption;
• increasing capital expenditure and operating expense requirements and Ameren Missouri's ability to recover these costs;
• the cost and availability of fuel such as coal, natural gas, and enriched uranium used to produce electricity; the cost and availability of purchased power and natural gas for distribution; and the level and volatility of future market prices for such commodities, including the ability to recover the costs for such commodities;
• the effectiveness of Ameren Missouri's risk management strategies and the use of financial and derivative instruments;
• the level and volatility of future prices for power in the Midwest;
• the development of a capacity market within the Midwest Independent Transmission System Operator, Inc. ("MISO") and the outcomes of MISO's inaugural capacity auction in 2013;
• business and economic conditions, including their impact on interest rates, bad debt expense, and demand for Ameren Missouri's products;
• disruptions of the capital markets, deterioration in Ameren Missouri's credit metrics, or other events that make Ameren Missouri's access to necessary capital, including short-term credit and liquidity, impossible, more difficult, or more costly;
• Ameren Missouri's assessment of its liquidity;
• the impact of the adoption of new accounting guidance and the application of appropriate technical accounting rules and guidance;
• actions of credit rating agencies and the effects of such actions;
• the impact of weather conditions and other natural phenomena on us and Ameren Missouri's customers;
• the impact of system outages;
• generation, transmission, and distribution asset construction, installation, performance, and cost recovery;
• the extent to which Ameren Missouri prevails in its claims against insurers in connection with its Taum Sauk pumped-storage hydroelectric energy center incident;
• the extent to which Ameren Missouri is permitted by its regulators to recover in rates the investments Ameren Missouri made in connection with a proposed second unit at its Callaway energy center;
• impairments of long-lived assets, intangible assets, or goodwill;
• operation of Ameren Missouri's Callaway nuclear energy center, including planned and unplanned outages, decommissioning, costs and potential increased costs because of Nuclear Regulatory Commission orders to address nuclear plant readiness as a result of nuclear-related developments in Japan in 2011;
• the effects of strategic initiatives, including mergers, acquisitions and divestitures, and any related tax implications;
• the impact of current environmental regulations on utilities and power generating companies and new, more stringent or changing requirements, including those related to greenhouse gases, other emissions, cooling water intake structures, coal combustion residuals, and energy efficiency, that are enacted over time and that could limit or terminate the operation of certain of Ameren Missouri's generating units, increase its costs, result in an impairment of its assets, reduce its customers' demand for electricity or natural gas, or otherwise have a negative financial effect;
• the impact of complying with renewable energy portfolio requirements in Missouri;
• labor disputes, workforce reductions, future wage and employee benefits costs, including changes in discount rates and returns on benefit plan assets;
• the inability of Ameren Missouri's counterparties and affiliates to meet their obligations with respect to contracts, credit facilities, and financial instruments;
• the cost and availability of transmission capacity for the energy generated by Ameren Missouri's energy centers or required to satisfy energy sales made by Ameren Missouri;
• legal and administrative proceedings; and
• acts of sabotage, war, terrorism, cybersecurity attacks or intentionally disruptive acts.

Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except to the extent required by the federal securities laws, Ameren Missouri undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

SOURCE Ameren Corporation