Rio Tinto Announces a Resource Increase of 628 Million Tonnes at Kennecott Utah Copper

Business Wire, May 16, 2008

LONDON -- Rio Tinto has further strengthened its global copper resources with the upgrade of mineral resources to 637 million tonnes at 0.48 per cent copper at its wholly owned Kennecott Utah Copper Bingham Canyon Mine. The resource is located beneath the current Bingham Canyon pit, and is currently under study for extraction by open pit mining methods. This represents an increase of 628 million tonnes over the December 2007 resource statement.

"We are very pleased with this substantial upgrade in resources. It will add significant value to Kennecott Utah Copper and Rio Tinto, particularly during this period of rapid long term demand growth," said Bret Clayton, chief executive, Rio Tinto Copper. "We are continuing with our pre-feasibility studies to examine options to develop these resources."

The Bingham Canyon mine is another example of the brownfield exploration potential within Rio Tinto's global portfolio. Over the past two years, exploration has identified a world class molybdenum deposit at depth underneath the current mine and there are multiple targets for further consideration within the Oquirrh Mountain range in Utah.

The resource upgrade at Bingham Canyon came through continuing mine planning, economic, and resource development studies. These studies are a part of an ongoing technical development programme, which includes new resource drilling and the study of open pit and underground mining options.

As the second largest copper producer in the United States, Kennecott Utah Copper provides about 13 per cent of US copper needs. Kennecott Bingham Canyon Mine, located in the Salt Lake City Valley, is the largest man-made excavation in the world. It has been in operation for more than 100 years and has produced more copper, 16.4 million tonnes, than any mine in the world. Every year, Kennecott produces approximately 272,000 tonnes of copper, along with 500,000 ounces of gold, 4 million ounces of silver, about 30 million pounds of molybdenum, and about 0.9 million tonnes of sulphuric acid, a by-product of the smelting process.

The resource at Bingham Canyon Mine has been generated to comply with the JORC code guidelines. The tabulated figures below show the new resource as classified, and the December 2007 resource position for comparison.

[TABLE OMITTED]

*Rio Tinto interest 100%

Note: Blank cells mean no resource in this category

Preliminary pit optimisation studies indicate that the reported resource falls within reach of an open-pit cutback to the existing Bingham Canyon mine operations. Continuation of the mine development studies to allow conversion of this resource to ore reserves is a high priority for the business and is scheduled for completion by the end of 2009.

CP statement

The information in this report that relates to Mineral Resources is based on information compiled by Jim Vickery, who is a member of the Australian Institute of Mining and Metallurgy. Jim is a full time employee of Kennecott Utah Copper and has experience which is relevant to the style of mineralisation and type of deposits under consideration and to the activity which he has undertaken to qualify as a Competent Person as defined in the 2004 Edition of the 'Australasian Code for Reporting of Exploration Results, Minerals Resources and Ore Reserves'. Jim Vickery consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.

About Rio Tinto

Rio Tinto is a leading international mining group headquartered in the UK, combining Rio Tinto plc, a London and NYSE 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.

Forward-Looking Statements

This announcement includes "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements other than statements of historical facts included in this announcement, including, without limitation, those regarding Rio Tinto's financial position, business strategy, plans and objectives of management for future operations (including development plans and objectives relating to Rio Tinto's products, production forecasts and reserve and resource positions), are forward-looking statements. Such forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Rio Tinto, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements.