• Voluntary tender offer of EUR 32.50 per share

• Transaction with an enterprise value of EUR 3.1 billion

• Celanese Management Board and main shareholder KPC support tender offer

BCP Crystal Acquisition GmbH & Co. KG, a German limited partnership controlled by a group of funds advised by The Blackstone Group, New York, today announced its decision to make a voluntary takeover offer (the “Offer”) for all of the outstanding shares of Celanese AG, Kronberg i.T. (WKN 575300). BCP Crystal Acquisition GmbH & Co. KG intends to offer a price per share of EUR 32.50. This is above the all-time-high closing price and represents a premium of 46% over the average daily volume-weighted price per share of Celanese in 2003, and a premium of 13% over the three-month volume-weighted average daily closing share price of EUR 28.66.

With a total transaction value of approximately EUR 3.1 billion including the value of Celanese’s current net debt and pension and post-retirement benefit obligations, this transaction is one of the largest transactions in 2003 and also the largest public-to-private offer in Germany to date. It is also the first dual jurisdiction tender offer in Germany and the US since the Takeover Act was enacted in Germany.

Celanese management is supportive of the Offer.

Stephen A. Schwarzman, President and CEO of The Blackstone Group, commented: “Blackstone views Celanese as an attractive vehicle for growth with ongoing opportunities for operational enhancements and execution of strategic initiatives, including acquisitions and restructurings. Blackstone believes that taking Celanese private will provide the Company with increased flexibility to more actively pursue its strategic objectives.”

Celanese AG’s largest shareholder, Kuwait Petroleum Corporation (“KPC”), holding approximately 29% of the shares of Celanese AG (excluding treasury shares), has undertaken to accept the tender offer.

The takeover offer will be conditioned on the receipt of antitrust clearances and will contain further conditions that will be described in the offering materials. BCP Crystal Acquisition GmbH & Co. KG expects that these conditions will include a minimum acceptance condition of 85% of the issued ordinary shares (excluding the treasury shares), the absence of any material adverse change with respect to Celanese AG and other, mostly customary, conditions. Blackstone will provide the equity funding for the transaction and Morgan Stanley and Deutsche Bank have provided firm financing commitments for the remaining funds required to complete the transaction.

In addition to its offer price of EUR 32.50 per share, BCP Crystal Acquisition GmbH & Co. KG also intends to arrange for a pre-funding of approximately $460 million (approximately EUR 380 million based on current exchange rates) into Celanese’s pension funds, covering a large part of the underfunding of those funds.

The Blackstone Group, a leading global investment firm, was founded in 1985. Blackstone Capital Partners IV is the largest institutional private equity fund ever raised at $6.45 billion. The firm has raised in excess of $25 billion for alternative asset investing since its formation, including over $14 billion for private equity investing. Blackstone is headquartered in New York. Blackstone is advised on its European investments by offices in London and Hamburg. The latter office was recently opened to advise on fund investments in the German speaking and Northern European markets. Blackstone´s policy is only to pursue strictly friendly transactions.

Celanese was spun off in 1999 from the former Hoechst AG and is a global industrial chemicals company that operates five principal business segments: Acetyl products; chemical intermediates; acetate products; Ticona and Nutrinova. Celanese had revenues of € 4.3bn in 2002, employing 10,700 world-wide. The share price of Celanese at the time of the spin off in 1999 was €16.

The offer document (Angebotsunterlage), when available, will be published by BCP Crystal Acquisition GmbH & Co. KG at the web site www.tbg-cag.de and in the Börsen Zeitung (or, on days on which the Börsen Zeitung is not published, in the Frankfurter Allgemeine Zeitung) after the approval by the Bundesanstalt für Finanzdienstleistungsaufsicht (“BAFin”). The offer document, when available, may also be obtained at the SEC’s website, www.sec.gov. The approval by BAFin is expected in early February 2004.

This announcement is neither an offer to purchase nor a solicitation of an offer to sell securities of Celanese AG. At the time the takeover offer is commenced, BCP Crystal Acquisition GmbH & Co. KG will file a tender offer statement with the U.S. Securities and Exchange Commission (SEC) with respect to the takeover offer. Investors and Celanese AG shareholders are strongly advised to read the tender offer statement and other relevant documents regarding the takeover offer filed by BCP Crystal Acquisition GmbH & Co. KG with the SEC when they become available because they will contain important information. Investors will be able to receive these documents, when they become available, free of charge at the SEC’s web site, www.sec.gov, or from BCP Crystal Acquisition GmbH & Co. KG at the web site www.tbg-cag.de.

Note regarding forward-looking statements. This news release contains “forward-looking statements.” Forward-looking statements may be identified by words such as “expects”, “anticipates”, “intends”, “plans”, “believes”, “seeks”, “estimates”, “will” or words of similar meaning and include, but are not limited to, statements about the expected future business of Celanese AG resulting from and following the proposed transaction. These statements are based on the current expectations of BCP Crystal Acquisition GmbH & Co. KG’s management, and are inherently subject to uncertainties and changes in circumstances. Among the factors that could cause actual results to differ materially from those described in the forward-looking statements are factors relating to satisfaction of the conditions to the proposed transaction, and changes in global, political, economic, business, competitive, market and regulatory forces. BCP Crystal Acquisition GmbH & Co. KG does not undertake any obligation to update the forward-looking statements to reflect actual results, or any change in events, conditions, assumptions or other factors.