Notification of Interests

Tullow Oil PLC
29 March 2005

                               TULLOW OIL PLC


                                  SCHEDULE 10

                   NOTIFICATION OF MAJOR INTERESTS IN SHARES

          
1.   Name of company

     Tullow Oil plc

2.   Name of shareholder having a major interest

     Merrill Lynch Investment Managers Group 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

     See 4 below


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

                                               Number               Beneficial
     Registered Holder                      of Shares                 Interest

     Nutraco Nominees
     Limited                               42,424,610                       No

     Merrill Lynch Pension 
     Nominees Ltd A/C Noncert               5,575,524                      Yes

     Treasury of the Government of 
     the Isle of Man Nominees A/C 5         1,351,397                       No

     Treasury of the Government of 
     the Isle of Man

     Nominees A/C 10                          629,946                       No

     Stamford Nominees
     Limited A/C CHARITY                      117,100                       No

     Other names                           27,903,842                       No

     Total                                 78,002,419


5.   Number of shares / amount of stock acquired

     Not disclosed


6.   Percentage of issued class

     Not Disclosed


7.   Number of shares / amount of stock disposed

     Not Disclosed


8.   Percentage of issued class

     Not Disclosed


9.   Class of security

     Ordinary 10p shares


10.  Date of transaction

     -


11.  Date company informed

     29 March 2005


12.  Total holding following this notification

     78,002,419


13.  Total percentage holding of issued class following this notification

     12.07%


14.  Any additional information
     
     Total shares in issue 646,179,868


15.  Name of contact and telephone number for queries

     Tom Hickey 0207 333 6800


16.  Name and signature of authorised company official responsible for making 
     this notification

     Tom Hickey


Date of notification

29 March 2005


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