Alcan offer commenced

Rio Tinto PLC
24 July 2007



Rio Tinto offer for Alcan commenced



Montreal, Melbourne and London (24 July 2007) - Rio Tinto plc and Alcan Inc.
announce that Rio Tinto Canada Holding Inc., an indirect wholly-owned subsidiary
of Rio Tinto, will today commence its offer for Alcan and mail its offer and
take-over bid circular to Alcan shareholders. The Alcan directors' circular
containing the Alcan board's unanimous recommendation to accept the Rio Tinto
Canada Holding offer is also being mailed to Alcan shareholders. Earlier this
month, Rio Tinto and Alcan reached an agreement for Rio Tinto Canada Holding to
make an offer to acquire all of Alcan's outstanding common shares for US$101 per
common share in a recommended, all cash transaction.



The offer represents a total consideration for Alcan common shares of
approximately US$38.1 billion.



The offer is open for acceptance until 6:00 pm (Eastern Time) on September 24,
2007, unless extended, and is subject to a number of conditions including valid
acceptances by holders of not less than 66 2/3 per cent of Alcan shares on
a fully diluted basis. The board of Rio Tinto has approved the transaction. The
offer is expected to close in the fourth quarter of 2007.



About Rio Tinto



Rio Tinto is a leading international mining group headquartered in the UK,
combining Rio Tinto plc, a London listed company, and Rio Tinto Limited, which
is listed on the Australian Securities Exchange.



Rio Tinto's business is finding, mining, and processing mineral resources. Major
products are aluminium, copper, diamonds, energy (coal and uranium), gold,
industrial minerals (borax, titanium dioxide, salt, talc) and iron ore.
Activities span the world but are strongly represented in Australia and North
America with significant businesses in South America, Asia, Europe and southern
Africa.





About Alcan



Alcan Inc. is a leading global materials company, delivering high quality
products, engineered solutions and services worldwide. With operations in
bauxite mining, alumina processing, primary metal smelting, power generation,
aluminium fabrication, engineered solutions as well as flexible and specialty
packaging, and with world class technology, Alcan is well positioned to meet and
exceed its customers' needs. Alcan is represented by 68,000 employees, including
its joint ventures, in 61 countries and regions.



For the year ended 31 December 2006, Alcan had audited consolidated revenues of
US$23,641 million (2005: US$20,320 million), and profit before taxation of
US$2,373 million (2005: US$323 million). Alcan had audited gross assets as at 31
December 2006 of US$28,939 million. The Alcan financial information presented
above has been extracted without material amendment from published financial
reports prepared under US GAAP.



Contacts



Rio Tinto


Media Relations

London                                               Australia

Nick Cobban                                          Ian Head
Office:  [phone]                        Office:  [phone]
Mobile: [phone]                         Mobile: [phone]
Christina Mills
Office:   [phone]
                                                     

                                                     
France                                               Canada/ USA
Tara Hopkins                                         Louie Cononelos
+ 33 1 41 05 44 57                                   Office:  [phone]
                                                     Mobile: [phone]

Investor Relations

London                                               Australia
Nigel Jones                                          Dave Skinner
Office:  [phone]                        Office:  [phone]
Mobile: [phone]                         Mobile: [phone]

David Ovington                                       Susie Creswell
Office:  [phone]                        Office:  [phone]
Mobile: [phone]                          Mobile: [phone]



Email: [e-mail]
Website: www.riotinto.com
High resolution photographs available at: www.newscast.co.uk




Alcan



Media contact                                         Investor contact


Anik Michaud                                          Ulf Quellmann
Office:  [phone]                              Office :  [phone]
[e-mail]                             [e-mail]




Additional information



IMPORTANT INFORMATION:



The offer to purchase all of the issued and outstanding common shares of Alcan
(the 'Offer') is being made by Rio Tinto Canada Holding Inc. (the 'Offeror'), an
indirect wholly-owned subsidiary of Rio Tinto.



This announcement is for information purposes only and does not constitute or
form part of any offer or invitation to purchase, otherwise acquire, subscribe
for, sell, otherwise dispose of or issue, or any solicitation of any offer to
sell, otherwise dispose of, issue, purchase, otherwise acquire or subscribe for,
any security. The Offer (as the same may be varied or extended in accordance
with applicable law) is being made exclusively by means of, and subject to the
terms and conditions set out in, the offer and takeover bid circular to be
delivered to Alcan and filed with Canadian provincial securities regulators and
the United States Securities and Exchange Commission (the 'SEC') and mailed to
Alcan shareholders.



The release, publication or distribution of this announcement in certain
jurisdictions may be restricted by law and therefore persons in such
jurisdictions into which this announcement is released, published or distributed
should inform themselves about and observe such restrictions.



In connection with the Offer, the Offeror will file with the Canadian securities
regulatory authorities and the SEC an offer and takeover bid circular as well as
ancillary documents such as a letter of transmittal and a notice of guaranteed
delivery and Alcan will file a directors' circular with respect to the Offer.
The Offeror will also file with the SEC a Tender Offer statement on Schedule TO
(the 'Schedule TO') and Alcan is expected to file with the SEC a Solicitation/
Recommendation Statement on Schedule 14D-9 (the 'Schedule 14D-9'). SHAREHOLDERS
OF ALCAN ARE URGED TO READ THE OFFER AND TAKEOVER BID CIRCULAR (INCLUDING THE
LETTER OF TRANSMITTAL AND NOTICE OF GUARANTEED DELIVERY), THE SCHEDULE TO
(INCLUDING THE OFFER AND TAKEOVER BID CIRCULAR, LETTER OF TRANSMITTAL AND
RELATED TENDER OFFER DOCUMENTS) AND THE SCHEDULE 14D-9 AS THEY WILL CONTAIN
IMPORTANT INFORMATION ABOUT THE OFFER.



The offer and takeover bid circular as well as other materials filed with the
Canadian securities regulatory authorities are available electronically without
charge at www.sedar.com. The Schedule TO and the Schedule 14D-9 will be
available electronically without charge at the SEC's website, www.sec.gov.
Materials filed with the SEC or the Canadian securities regulatory authorities
may also be obtained without charge at Rio Tinto's website, www.riotinto.com.



While the Offer is being made to all holders of Alcan common shares, this
announcement does not constitute an offer or a solicitation in any jurisdiction
in which such offer or solicitation is unlawful. The Offer is not being made in,
nor will deposits be accepted in, any jurisdiction in which the making or
acceptance thereof would not be in compliance with the laws of such
jurisdiction. However, the Offeror may, in its sole discretion, take such action
as they may deem necessary to extend the Offer in any such jurisdiction.



In France, an announcement including the main information relating of the offer
documents will be prepared and released pursuant to article 231-24 of the AMF
General Regulation and will contain information for Alcan shareholders residing
in France relating to how to accept, and the time limit for acceptance of this
Offer.

A Belgian supplement, addressing issues specific to holders of Alcan ordinary
shares and/or International Depositary Receipts (IDRs) in Belgium (the 'Belgian
Supplement') is expected to be approved, together with the Offer Document, by
the Belgian Banking, Finance and Insurance Commission. Until such approval has
been obtained, the Offer cannot be made in Belgium to any holder of Alcan
ordinary shares and/or IDRs. Once such approval has been obtained, the Offer
Document will be made available in Belgium to all holders of Alcan ordinary
shares and/or IDRs together with the Belgian Supplement, and the Offer will be
made to such holders.



Forward looking statements



This announcement may contain statements which constitute 'forward-looking
statements' about Rio Tinto and Alcan. Such statements include, but are not
limited to, statements with regard to the outcome of the Offer, and may be (but
are not necessarily) identified by the use of phrases such as 'will', 'intend',
'estimate', 'expect', 'anticipate', 'believe' and 'envisage'.  By their nature,
forward-looking statements involve risk and uncertainty because they relate to
events and depend on circumstances that will occur in the future and may be
outside the control of Rio Tinto or Alcan. Actual results and developments may
differ materially from those expressed or implied in such statements because of
a number of factors, including the outcome of the Offer, revenue benefits and
cost synergies being lower than expected, integration costs being higher than
expected, levels of demand and market prices, the ability to produce and
transport products profitably, the impact of foreign currency exchange rates on
market prices and operating costs, operational problems, political uncertainty
and economic conditions in relevant areas of the world, the actions of
competitors, activities by governmental authorities such as changes in taxation
or regulation and such other risk factors identified in Rio Tinto's most recent
Annual Report on Form 20-F filed with the SEC or Form 6-Ks furnished to the SEC
or Alcan's most recent periodic and current reports on Form 10-K, Form 10-Q or
Form 8-K filed with the SEC (as the case may be). Forward-looking statements
should, therefore, be construed in light of such risk factors and undue reliance
should not be placed on forward-looking statements.





Other than in accordance with their legal and regulatory obligations (including,
in the case of Rio Tinto, under the UK Listing Rules and the Disclosure and
Transparency Rules of the Financial Services Authority), neither Rio Tinto nor
Alcan is under any obligation and each of Rio Tinto and Alcan expressly disclaim
any intention or obligation to update or revise any forward-looking statements,
whether as a result of new information, future events or otherwise.






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