Holding(s) in Company

Tullow Oil PLC
20 December 2006


                      Tullow Oil plc ('Tullow')

                         Holding in Company


On 20 December 2006, Tullow was notified by Merrill Lynch & Co., Inc that as at
8 December 2006 it and BlackRock Inc. had an aggregate interest in 97,724,283
ordinary shares of 10 pence each in Tullow, representing approximately 14.99% of
Tullow's current issued ordinary share capital and that each company named below
is interested in the number of shares against its name;

Company                                               Number of Shares

Merrill Lynch & Co.,Inc                               1,043,865
BlackRock Group                                       96,680,418
Aggregated total                                      97,724,283



20 December, 2006


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