Exploration Update

Tullow Oil PLC
22 August 2007



Ghana Exploration Update - Hyedua-1 well, Deepwater Tano

22 August 2007 - Tullow Oil plc (Tullow) announces that the Hyedua-1 well,
drilled on the Deepwater Tano licence offshore the Republic of Ghana, has
discovered a significant light oil accumulation based on the results of
drilling, wireline logs and samples of reservoir fluid. Initial data from the
well indicates that the Hyedua-1 and Mahogany-1 wells are likely to represent a
single continuous trap extending across the West Cape Three Points and Deepwater
Tano blocks. Tullow operates the Deepwater Tano licence (49.95%) and also holds
an interest in the West Cape Three Points licence (22.9%).

Hyedua-1 is being drilled as the initial exploration well on the Deepwater Tano
licence. The well is targeting the equivalent Santonian turbidite sandstones
encountered in the Mahogany-1 discovery well located some 5.3km to the northeast
of Hyedua-1 on the adjacent West Cape Three Points licence.  It is being drilled
by the 'Belford Dolphin' deepwater drillship in water depths of 1,530m and has
been drilled to a total depth of 4,002m.

The well has encountered a gross reservoir interval of 202m, containing 108m of
high quality stacked reservoir sandstones, and net hydrocarbon-bearing pay of
41m. In addition, the results of logging and pressure testing indicate the
strong likelihood that the reservoir sands are in communication with the
Mahogany discovery, indicating combined hydrocarbon columns in excess of 361m
within a continuous accumulation which extends across the Deepwater Tano and
West Cape Three Points licences.  The well will now be sidetracked, prior to
casing, to acquire core data over the reservoir interval and suspended for
potential use as a development well.

Planning is already under way to rapidly appraise the accumulation.  Suitable
vessels have been identified to carry out a 910 sq km high-resolution 3D seismic
survey, covering the combined feature on both the Deepwater Tano and West Cape
Three Points blocks, and a programme of up to three additional appraisal wells
in late 2007.

Tullow's partners in the Deepwater Tano licence are Kosmos Energy and a
subsidiary of Anadarko Petroleum Corporation, (18% each), Sabre Oil & Gas
(4.05%) and the Ghana National Petroleum Corporation (GNPC) (10% carried
interest).

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

'The discovery of oil in Hyedua-1, and the confirmation of its communication
with the recent Mahogany discovery, represents a major step forward for the
Republic of Ghana and for Tullow and its partners. It significantly enhances our
understanding of the resource, enables us to focus and accelerate our appraisal
programme, and is highly encouraging for our plans to establish commercial
production in Ghana. '


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
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 250 Index. The Group has interests in over 120
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.

In Africa, Tullow has exploration and production in Gabon, Cote d'Ivoire, Congo
(Brazzaville), Mauritania and Equatorial Guinea and a large gas field
development and appraisal programme in Namibia. Tullow also has exploration
programmes in Mauritania, Senegal, Cameroon, Uganda, Congo (DRC), Tanzania,
Madagascar, Angola and Ghana. In Ghana, in addition to the two deepwater
licences, Tullow also holds a 31.5% interest, as Operator, in another separate
licence, Shallow Water Tano, which is not the subject of this release but where
a well is due to be spudded within the next few weeks.

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, Suriname and the Falkland Islands.



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

                                      ENDS


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