The website that you are entering contains information relating to Alcan's U.S. exchange offer for the outstanding securities of Pechiney (the "Offer"). The Offer has been registered with the U.S. Securities and Exchange Commission and is being made on the basis of Alcan's Prospectus, dated October 24, 2003 (the "Prospectus"), which contains detailed information about the Offer and about Alcan, including financial statements. An electronic copy of the Prospectus is available on this website. The Prospectus and the information incorporated by reference in the Prospectus may be also be obtained by calling D.F. King & Co., Inc., toll-free at (800) 488-8035. Neither this website nor any other information contained on this website is a part of that Prospectus.

The information on this website is not an offer to sell securities or the solicitation of an offer to buy securities, nor shall there be any offer or sale of securities in, any jurisdiction in which such offer or sale would be unlawful.

In order to access this website, you must certify that you are (i) a holder of Pechiney common shares, Pechiney Bonus Allocation Rights or Pechiney OCEANEs (obligations à option de conversion en actions nouvelles et/ou d'échange en actions existantes) located in the United States of America or Canada, or/and (ii) a holder of Pechiney American Depositary Shares.

Yes, I agree

By checking this box I certify that I am either (i) a holder of Pechiney common shares, Pechiney Bonus Allocation Rights or Pechiney OCEANEs (obligations à option de conversion en actions nouvelles et/ou d'échange en actions existantes) located in the United States of America or Canada, or/and (ii) a holder of Pechiney American Depositary Shares

FORWARD-LOOKING STATEMENTS

Certain statements made in this communication are forward-looking statements. Although Alcan's management believes that the expectations reflected in such forward-looking statements are reasonable, readers are cautioned that these forward-looking statements by their nature involve risk and uncertainty because they relate to events and depend on circumstances that will occur in the future. Many factors could cause actual results and developments to differ materially from those expressed or implied by these forward-looking statements, including those listed under "Cautionary Statement Concerning Forward-Looking Statements" and "Risk Factors" in the prospectus included in the registration statement we have filed with the SEC in connection with our proposed offer for certain securities of Pechiney. See the previous paragraphs for information about how you can obtain a free copy of the registration statement.

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This site includes certain information concerning Pechiney and the combined business of Alcan and Pechiney. This information is subject to risks and uncertainties. We have based this information on publicly available information about Pechiney (primarily filings by Pechiney with the Securities and Exchange Commission and the French Commission des Opérations de Bourse). However, Pechiney has not granted Alcan access to Pechiney's books and records or any other non-public information regarding Pechiney and Alcan has no means of compelling such access. In addition, Pechiney's primary financial statements are prepared in accordance with generally accepted accounting principles ("GAAP") in France while Alcan's primary financial statements are prepared in accordance with Canadian GAAP. There are differences between Canadian and French GAAP, and it is not possible for us to prepare Canadian GAAP pro forma information without Pechiney's cooperation. The unaudited pro forma information included herein is prepared based on the limited US GAAP information that Pechiney discloses publicly. In these circumstances Alcan is not in a position to verify the Pechiney information or the pro forma information about the combined entity. Some of the information about Pechiney is based on good faith estimates by Alcan or industry sources that may be materially inaccurate. The pro forma information presented is not necessarily indicative of the operating results or financial condition that would have been achieved had Alcan's offer for Pechiney been completed during the periods or at the times presented, nor is this information necessarily indicative of future results or conditions of Alcan after it has acquired Pechiney. The pro forma information does not reflect the impact of synergies that Alcan expects to realize over time or the costs associated with the integration of operations necessary to achieve such synergies nor does it reflect the impact of significant divestitures that Alcan expects to undertake to complete in order to receive required clearances with antitrust regulators. Some of the risks associated with the information about Pechiney and the combined Alcan and Pechiney will be discussed under "Risk Factors" in the preliminary prospectus included in the registration statement that we intend to file with the SEC in connection with the proposed offer.

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ALCAN & PECHINEY, BRINGING THE FUTURE CLOSER

The globalization of markets underscores the fact that there is strength in unity.
The friendly tender offer launched by Alcan for Pechiney is based on sound industrial logic.

By joining their respective strengths, Alcan and Pechiney will form a world leader in the aluminium and packaging industry.

The combined company will benefit from enhanced financial strength, broader technological resources and a diversified product portfolio.

In keeping with its social and industrial commitments, the Alcan Group invites you to take part in a project that has compelling value for all stakeholders.

Alcan and Pechiney already share a long history, as well as common professions, experiences and unique expertise.

Thus, by joining forces, Alcan and Pechiney will be in a position to optimize their know-how and reinforce a policy of innovation that is key to a strategy of sustainable development. Moreover, the undeniable industrial and geographic compatibility of these two groups in Europe and North America holds forth the promise of solid growth for the combined entity.

The organization of the combined company will take into account the respective areas of excellence of both groups. The company's worldwide headquarters for its packaging and aerospace operations and engineered products will be located in France, which will also be the site of the European headquarters for its primary aluminum and smelting operations. France will also be the future home of the company's global centre for the development of new cell technology for primary aluminum.

Finally, Alcan and Pechiney are already joined by their strong commitment to values such as integrity, responsibility, confidence, transparency and teamwork. These are all values that Alcan will henceforth place in the service of a shared ambition, of a project that creates value for the company, its customers, partners, employees and shareholders.

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Sincerely,

Travis Engen
President and Chief Executive Officer

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1.Bauxite, Alumina and Specialty Chemicals
Alcan will benefit from a doubling of its ownership in Queensland Alumina Ltd., the largest and one of the lowest cost aluminum producers in the world. The Company will also benefit from the ability to extend and improve its alumina production technology.

2.Primary aluminum
Alcan expects to benefit from the combined entity's larger low-cost position and opportunities for low-cost growth in primary aluminum production based on, among other things, increased opportunities to sustain and enhance Pechiney's strong position in new cell, high-amperage smelting technology and to extend its implementation.

3.Rolled products
The addition of Pechiney's fabrication operations will provide Alcan with opportunities to participate, with a strong global position, in the specialized and strategic aerospace market and increase productivity through global implementation of best practices and the usage of the world-class rolling technologies of both companies.

4.Engineered Products
The addition of Pechiney's operations in engineered products will enable Alcan to better serve the expanding demand for aluminum applications in the automotive industry, in both North America and Europe.

5.Packaging
The combination of Alcan's and Pechiney's flexible and specialty packaging businesses will create one of the largest packaging companies in the world with a leading position in flexible packaging, complementary market positions in North America and Europe, and a strong range of value-added products.

6.Technology
Following the transaction, Alcan intends to continue to support Pechiney's technology facilities with continued and enhanced investments to further develop its world leading technologies, particularly in aluminum smelting. Specifically, Alcan plans to retain and enhance Pechiney's research and development capabilities in France, where it has established and nurtured a recognized global center of excellence.

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