Operations Update

Tullow Oil PLC
06 May 2008

News release



Operations Update - Successful Mahogany-2 appraisal well


6 May 2008 - Tullow Oil plc (Tullow) announces that the Mahogany-2 well, which
is being drilled to appraise the Jubilee field offshore Ghana, has intersected a
significant column of light oil. Results of drilling, wireline logs and samples
of reservoir fluid, indicate that Jubilee is a single continuous stratigraphic
trap extending at least 11km to the Hyedua-1 discovery well in the adjacent
Deepwater Tano licence.


Mahogany-2, which lies in the West Cape Three Points licence, is the first
appraisal well on the Jubilee field and is targeting the Turonian turbidite
sandstones encountered in the   Mahogany-1 and Hyedua-1 discovery wells. The
well has encountered a gross reservoir interval of 243 metres, containing 63
metres of high quality stacked reservoir sandstones, and net hydrocarbon-bearing
pay of 50 metres. Results of logging and pressure testing indicate that the
combined hydrocarbon columns are in excess of 600 metres.


Analysis of the oil samples from the Mahogany-1 discovery well had suggested the
potential for a gas cap at the Mahogany-2 location. No gas cap has however been
encountered in this well thereby indicating the potential for the Jubilee field
to extend further up-dip of this location.


A limited flow test will now commence on Mahogany-2 to determine potential
production rates from these excellent quality reservoirs and to collect further
oil samples for analysis. Testing is expected to take approximately four weeks
and the well will then be suspended for use as a potential development well.


Mahogany-2 has been drilled to a total depth of 3,443 metres by the Songa Saturn
drillship in water depths of 1,080 metres. Three more Jubilee appraisal wells
are planned for 2008 and will be drilled by the Blackford Dolphin
semi-submersible. The next Jubilee appraisal well, Hyedua-2, is expected to
commence in July in the adjacent Deepwater Tano licence in which Tullow has a
49.95% interest.


Tullow has a 22.9% interest in the West Cape Three Points licence. Other
partners include Kosmos Energy (Operator 30.875%), Anadarko Petroleum (30.875%),
the E.O.Group (3.5%), Sabre Oil & Gas (1.854%) and the Ghana National Petroleum
Corporation (GNPC) (10% carried interest). Tullow is the Unit Operator of the
Jubilee field.



Commenting today, Aidan Heavey, Chief Executive of Tullow said:

'The confirmation that Mahogany-2 is in communication with both Mahogany-1 and
Hyedua-1, reinforces our interpretation that Jubilee is a major discovery and is
likely to lead to a material upgrade of current resource estimates. We will
continue our appraisal and development programme over the remainder of 2008 with
the overall objective of achieving first production in 2010.'

For further information contact:
Tullow Oil plc                     Citigate Dewe Rogerson              Murray Consultants
([phone])                 ([phone])                  ([phone])
Aidan Heavey                       Martin Jackson                      Joe Murray
Tom Hickey                         Kate Delahunty                      Ed Micheau
Chris Perry



Notes to Editors

Tullow is a leading independent oil & gas, exploration and production group,
quoted on the London and Irish Stock Exchanges (symbol: TLW) and is a
constituent of the FTSE 100 Index. The Group has interests in over 100
exploration and production licences across 23 countries and focuses on four core
areas: Europe, Africa, South Asia and South America.


Tullow's European interests are primarily focused on gas in the UK Southern
North Sea where it has significant interests in the Caister-Murdoch System and
the Thames-Hewett areas and operates over 70% of its production. The company
also has interests offshore the Netherlands and Portugal.


In Africa, Tullow has exploration and production in Gabon, Cote d'Ivoire,
Mauritania and Equatorial Guinea and two large appraisal and development
programmes in Ghana and Uganda. Tullow also has exploration interests in
Mauritania, Senegal, Congo (DRC), Tanzania, Madagascar, Namibia and Angola.


In South Asia, Tullow has exploration and production in Pakistan and Bangladesh
and high impact exploration activities in India.


In South America Tullow has high impact exploration interests in Trinidad and
Tobago, French Guiana and Suriname.

For further information please refer to our website at www.tullowoil.com



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