RNS Number:5533O
International Power PLC
11 August 2003



Schedule 10 - Notification of Major Interests in Shares


1   Name of company:

International Power plc


2   Name of shareholder having a major interest:

Merrill Lynch Investment Managers Limited


3   Please state whether notification indicates that it is in respect of holding
of the shareholder named in 2 above or in respect of a non-beneficial interest
or in the case of an individual holder if it is a holding of that person's
spouse or children under the age of 18:

As above


4   Name of registered holder(s) and, if more than one holder, the number of
shares held by each of them:

Nutraco Nominees Limited

(Designated & Undesignated)                 71,317,472

Possfund (MAM) Nominees Limited                523,582

Britel (MAM) Nominees Limited                  635,875

Merrill Lynch Pensions Nominees Limited

A/C NONCERT                                  7,955,338

Merrill Lynch Pensions Nominees Limited          5,000

Treasury of the Government
of the Isle of Man

A/C 5                                          784,569

Treasury of the Government
of the Isle of Man

A/C 10                                         346,776
Stamford Nominees

A/C CHARTY                                     195,100

Chase Nominees Limited                      11,553,455

Nortrust Nominees Limited                   11,158,216

Bank of New York Nominees Limited            4,265,627

Junction Nominees Limited                   13,294,457

State Street Nominees Limited                1,616,887

Morgan Nominees Limited                      1,026,775

Other Names                                  8,930,574


5   Number of shares/amount of stock acquired:

Not known


6   Percentage of issued class:

Not known


7   Number of shares/amount of stock disposed:

Not known


8   Percentage of issued class:

Not known


9   Class of security:

Ordinary shares of 50 pence each


10  Date of transaction:

Not known


11  Date company informed:

11 August 2003


12  Total holding following this notification:

133,609,703


13  Total percentage holding of issued class following this notification:

12.01%


14  Contact name for queries:

1.  Investors                             Grant Jones
2.  Media                               Aarti Singhal


15 Contact telephone number:

1.  44-207-320-8619
2.  44-207-320-8681


16  Name of company official responsible for making notification:

Stephen Ramsay - Company Secretary


17  Date of notification:

11 August 2003


                      This information is provided by RNS
            The company news service from the London Stock Exchange
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