Exhibit 99.1

CMS ENERGY REACHES AGREEMENT TO SELL CMS PANHANDLE COMPANIES FOR $1.8 BILLION TO
SOUTHERN UNION PANHANDLE

   Proceeds To Accelerate Debt Reduction and Bolster Liquidity Improvement Plan

   DEARBORN, Mich., Dec. 22 /PRNewswire-FirstCall/ -- CMS Energy (NYSE: CMS)
   announced today that it has reached a definitive agreement to sell CMS
   Panhandle Companies, its interstate natural gas pipeline business and
   accompanying subsidiaries, to Southern Union Panhandle for $1.828 billion.

   The agreement calls for Southern Union Panhandle -- a newly formed entity
   owned by Southern Union Company (NYSE: SUG) and AIG Highstar Capital, L.P. --
   to pay $662 million in cash and assume $1.166 billion in debt.

   CMS Energy intends to use the proceeds to accelerate debt reduction. The
   Company has reduced its debt by $860 million in 2002, including paying down
   $239 million in bank debt since July.

   The transaction has been approved by the Board of Directors of each company
   and is subject to customary closing conditions, action by the Federal Trade
   Commission under the Hart-Scott-Rodino Act, and by appropriate state
   regulators.

   "This sale is a significant step forward in our efforts to increase our
   financial flexibility. With this agreement, CMS Energy has sold or announced
   $3.6 billion in asset sales in 2002. Clearly, we are executing our asset
   sales plan, despite difficult market conditions," said Ken Whipple, CMS
   Energy chairman and chief executive officer. "We will continue to pursue
   strategies that support our back-to-basics approach and our focus on
   improving our balance sheet, reducing risk, and strengthening our liquidity."

   The Company announced August 7, 2002, that it was exploring the sale of CMS
   Panhandle Companies and other businesses in order to accelerate balance sheet
   improvement and enhance financial flexibility. Merrill Lynch & Co. acted as
   financial advisor to CMS in conjunction with a competitive sales process
   related to the divestiture of CMS Panhandle Companies.

   The CMS Panhandle Companies include CMS Panhandle Eastern Pipe Line Company,
   CMS Trunkline Gas Company, CMS Trunkline LNG Company, which operates an LNG
   terminal complex at Lake Charles, La., and CMS Sea Robin Pipeline Company.
   The present book value of these assets is approximately $2.4 billion. As
   previously announced on November 14, 2002, the Company expects to write off
   most of the goodwill associated with the CMS Panhandle Companies in the
   fourth quarter under the new accounting standard SFAS No. 142. After this
   adjustment, the book value of the assets will be materially closer to the
   $1.8 billion sale price.

   Under terms of the sales agreement, CMS Energy retains its ownership
   interests in the Centennial refined petroleum liquids pipeline, which
   stretches from Texas to Illinois, and the Guardian natural gas pipeline,
   which serves northern Illinois and southern Wisconsin and entered service on
   Dec. 7, 2002. CMS Energy owns a one-third interest in each and is exploring
   the sale of those interests.

   Southern Union Panhandle is owned by Southern Union Company and AIG Highstar
   Capital, L.P. Southern Union is an international energy distribution company
   serving nearly 1.5 million customers in Texas, Missouri, Pennsylvania, Rhode
   Island, Massachusetts and Mexico. AIG Highstar Capital, L.P. is a private
   equity fund sponsored by American International Group, Inc. to make
   structured equity investments in infrastructure related projects and
   operating companies.

   CMS Energy Corporation is an integrated energy company, which has as its
   primary business operations an electric and natural gas utility, natural gas
   pipeline systems and independent power generation.

   For more information on CMS Energy, please visit our web site at:
   http://www.cmsenergy.com .

   This news release contains "forward-looking statements" within the meaning of
   the safe

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   harbor provisions of the federal securities laws. It should be read in
   conjunction with the forward-looking statements cautionary factors in CMS
   Energy's Securities and Exchange Commission filings that identify important
   factors that could cause CMS Energy's results to differ materially from those
   anticipated in such statements.


Source:  CMS Energy Corporation

Media Contacts -  Dan Bishop, 1-517-788-2395, or John Barnett, 1-713-989-7556 or
Investment Analyst Contact - CMS Energy Investor Relations, 1-517-788-2590.


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