NOT FOR DISTRIBUTION TO U.S. NEWS WIRE SERVICES OR FOR DISSEMINATION IN THE UNITED
STATES, AUSTRALIA, CANADA OR JAPAN

Norsk Hydro ASA (Hydro) has today published the prospectus in connection with its fully
underwritten rights issue, the terms and conditions for which where were announced on
June 21, 2010. The prospectus has been reviewed and approved by the Financial
Supervisory Authority of Norway.

Subscription price
The subscription price is NOK 26.30 per new share. Each existing shareholder will
receive 7 subscription rights for every 23 existing shares held based on their
shareholdings at the end of June 21, 2010 as registered in the Norwegian Central
Securities Depository (VPS) as of June 24, 2010.

Subscription period
From and including June 25, 2010 until July 9, 2010 at 17:30 hours (Oslo time)

Trading in subscription rights
From and including June 25, 2010 until July 6, 2010 at 17:30 hours (Oslo time)

Note that subscription rights that are not used to subscribe for new shares before the
end of the subscription period or not sold before July 6, 2010 at 17:30 (Oslo time) will
lapse without compensation and consequently be of no value.

Subject to applicable local securities laws, the prospectus will be sent by mail to all
shareholders registered in the VPS as of June 24, 2010, with the exception of those
subscribing to electronically receive messages from the company, who will receive this
information on e-mail or through “VPS investortjenester”. The prospectus is also
available at www.hydro.com/rightsissue http://www.hydro.com/rightsissue and
www.dnbnor.no/emisjoner http://www.dnbnor.no/emisjoner . The prospectus can also be
obtained from DnB NOR Markets.

Investor contact in Hydro
Contact Stefan Solberg
Cellular +47 91727528
E-mail Stefan.Solberg@hydro.com mailto:Stefan.Solberg@hydro.com

Press contact in Hydro
Contact Halvor Molland
Cellular +47 92979797
E-mail Halvor.Molland@hydro.com mailto:Halvor.Molland@hydro.com

Contact DnB NOR Markets
Telephone +47 91508940
E-mail markets.cf@dnbnor.no

*********
This announcement is not an offer for sale of securities in the United States or any
other country. The securities referred to herein have not been registered under the U.S.
Securities Act of 1933, as amended (the “U.S. Securities Act”), and may not be sold in
the United States absent registration or pursuant to an exemption from registration
under the U.S. Securities Act. Hydro does not intend to register any portion of the
offering of the securities in the United States or to conduct a public offering of the
securities in the United States. Any offering of securities will be made by means of a
prospectus that may be obtained from Hydro and that will contain detailed information
about the company and management, as well as financial statements. Copies of this
announcement are not being made and may not be distributed or sent into the United
States, Canada, Australia, Japan or any other jurisdiction in which such distribution
would be unlawful or would require registration or other measures.

In any EEA Member State that has implemented Directive 2003/71/EC (together with any
applicable implementing measures in any member State, the “Prospectus Directive”), this
communication is only addressed to and is only directed at qualified investors in that
Member State within the meaning of the Prospectus Directive.

This announcement is only directed at (a) persons who are outside the United Kingdom; or
(b) investment professionals within the meaning of Article 19 of the Financial Services
and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”); or (c) persons
falling within Article 49(2)(a) to (d) of the Order; or (d) persons to whom any
invitation or inducement to engage in investment activity can be communicated in
circumstances where Section 21(1) of the Financial Services and Markets Act 2000 does
not apply.

Certain statements included within this announcement contain forward-looking
information, including, without limitation, those relating to (a) forecasts, projections
and estimates, (b) statements of management’s plans, objectives and strategies for
Hydro, such as planned expansions, investments or other projects, (c) targeted
production volumes and costs, capacities or rates, start-up costs, cost reductions and
profit objectives, (d) various expectations about future developments in Hydro’s
markets, particularly prices, supply and demand and competition, (e) results of
operations, (f) margins, (g) growth rates, (h) risk management, as well as (i)
statements preceded by “expected”, “scheduled”, “targeted”, “planned”, “proposed”,
“intended” or similar statements.

Although we believe that the expectations reflected in such forward-looking statements
are reasonable, these forward-looking statements are based on a number of assumptions
and forecasts that, by their nature, involve risk and uncertainty. Various factors
could cause our actual results to differ materially from those projected in a
forward-looking statement or affect the extent to which a particular projection is
realized. Factors that could cause these differences include, but are not limited to:
our continued ability to reposition and restructure our upstream and downstream
aluminium business; changes in availability and cost of energy and raw materials; global
supply and demand for aluminium and aluminium products; world economic growth, including
rates of inflation and industrial production; changes in the relative value of
currencies and the value of commodity contracts; trends in Hydro’s key markets and
competition; and legislative, regulatory and political factors.

No assurance can be given that such expectations will prove to have been correct. Hydro
disclaims any obligation to update or revise any forward-looking statements, whether as
a result of new information, future events or otherwise.