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EXHIBIT NO. 99.1: PRESS RELEASE OF ALCAN ALUMINIUM LIMITED,
DATED SEPTEMBER 16, 1999

                        ALCAN, PECHINEY AND ALGROUP SIGN
                   DEFINITIVE THREE-WAY COMBINATION AGREEMENT

   PECHINEY COMPLETES WORKERS' COUNCILS INFORMATION AND CONSULTATION SESSIONS

                           --------------------------

     MONTREAL, CANADA; PARIS, FRANCE; AND ZURICH, SWITZERLAND - [SEPTEMBER 16,
1999] - Alcan (NYSE, TSE: AL), Pechiney (NYSE, PARIS: PY) and algroup (SWX:
ALUN), today jointly announced that, as anticipated in their August 11
announcement, they have now entered into a definitive three-way combination
agreement.

     The three companies announced the signing of a memorandum of understanding
("MoU") on August 11, with Alcan and algroup also having signed a definitive
two-way combination agreement. On its part, Pechiney was required, under French
law, to inform and consult its workers' councils prior to entering into a
definitive three-way combination agreement. That information and consultation
process was completed within the anticipated time frame and the two-way
combination agreement between Alcan and algroup has been replaced by the
three-way agreement such that one agreement now governs the three parties.

     As announced on August 11, the three-way merger will be accomplished
through two independent exchange offers that the parties have agreed will be
initiated by Alcan. Completion of the transaction will be subject to certain
conditions, the most relevant of which are:

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          (i) approval of the required share issuance at a meeting of Alcan
     shareholders, which is expected to be held in late October or early
     November;

          (ii) minimum acceptance thresholds of 67% by the shareholders of each
     of Pechiney and algroup in response to respective exchange offers, and;

          (iii) regulatory clearances and requirements.

     The completion of the algroup transaction also depends upon algroup
completing the announced tax-free demerger of its chemical and energy business
which is subject to the approval of its shareholders, anticipated to be obtained
at a meeting to be held in late October.

     Filings in respect of regulatory clearances have been made in the United
States and Canada and, with the signing of the three-way combination agreement,
will now be made in Europe. Regulatory filings are also being pursued in a
number of other jurisdictions. The parties confirm that the overall transaction
time frame remains on track with completion of all aspects expected for early
next year.

     With combined 1998 revenue of US$21.6 billion and operations in 59
countries, the merger of Alcan, Pechiney and algroup will create one of the
world's largest aluminium companies and the global leader in both flexible and
specialty packaging. The Alcan-Pechiney-algroup combination, temporarily to be
referred to as A.P.A, will be a world leader in aluminium, with complementary
operations and technologies, a sustainable superior low-cost position in primary
aluminium, superior aluminium fabricating positions globally, and superior
positioning for future low-cost growth and expansion. A.P.A. will bring together
highly complementary packaging businesses with leading positions in attractive
growth business areas including pharmaceuticals, food and cosmetics.

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     Additional information with respect to the three companies is contained in
their respective securities regulatory filings and financial statements. This
press release does not constitute an offering of securities, which may be made
by prospectus only. Detailed information with respect to the proposed three-way
combination agreement will be contained in the various formal documents,
including circulars, offers, registration statements and similar documents, to
be filed with securities regulatory authorities and sent to the shareholders of
the three companies.

                        CONTACTS FOR FURTHER INFORMATION



                                                
ALCAN
INVESTOR RELATIONS:                                MEDIA RELATIONS:
Alan Brown                                         Mathieu Bouchard
514-848-8368                                       514-848-8186

PECHINEY
INVESTOR RELATIONS:                                CORPORATE COMMUNICATIONS:
Francois-Jose Bordonado                            Jean-Claude Nicolas
33-1-5628-2507                                     33-1-5628-2422

ALGROUP
INVESTOR RELATIONS:                                CORPORATE COMMUNICATIONS:
Michel Gerber                                      Christine Menz
41-1-386-2314                                      41-1-386-2495



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