Holding(s) in Company

Tullow Oil PLC
24 August 2005


                   Tullow Oil plc ('Tullow' or 'the Company')

                              Holding in Company


On 23 August 2005, Tullow received notification that Merrill Lynch & Co., Inc
has a notifiable interest in 91,064,904 ordinary shares of 10p each in the
Company which represents 14.08% of the issued share capital of Tullow.

This total holding is held by a number of holding companies of Merrill Lynch
Investment Managers Limited and by certain other companies. Of the 91,064,904
ordinary shares in which Merrill Lynch & Co., Inc has a notifiable interest ,
Merrill Lynch Investment Managers Limited has a notifiable interest of
89,945,104 shares (13.91%). By virtue of a separate holding of 3,700 ordinary
shares Merrill Lynch Group, Inc has a notifiable interest of 89,948,804 ordinary
shares (13.91%)

Tullow has been informed that the shares held by Merrill Lynch Investment
Managers Limited to which this notification relates are registered as follows:

Registered Holder                       Number          Beneficial
                                      Of Shares          Interest

Nutraco Nominees Limited             44,519,459             No

Merrill Lynch Pension                 5,229,624            Yes
Nominees Ltd A/C Noncert

Treasury of the                       1,190,397             No
Government of the Isle of Man
Nominees A/C 5
                                                       
Treasury of the                         666,046             No
Government of the Isle of Man
Nominees A/C 10

Stamford Nominees                       223,900             No
Limited A/C CHARITY

Other names                          38,115,678             No

Total                                89,945,104


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