Wells Update

Tullow Oil PLC
20 December 2005

News release

Tullow Oil plc - Drilling Update


20th December 2005 - Tullow Oil plc (Tullow) announces updates on recent
drilling activities in Mauritania and Angola.



A full update on the rest of Tullow's activities will be provided in our Trading
Statement and Operational Update on 31 January 2006.



MAURITANIA BLOCK 1 - Faucon-1 Exploration Well (Tullow 20%)



Drilling on the Faucon-1 exploration well in Block 1 offshore Mauritania has now
been completed.  The well reached a total depth of 4,170m and encountered a
total of 96.5m of potential reservoir of which the upper 14m is hydrocarbon
bearing.  The hydrocarbon fluid composition will not be finally determined until
the downhole pressurised fluid samples recovered from the well have been fully
analysed in an onshore laboratory in January 2006.  The well will now be plugged
and abandoned.



ANGOLA BLOCK 10 - Ngueve-1 and Henda-1 Exploration Wells (Tullow 15%)



The two well exploration programme in Block 10 offshore Angola has now concluded
with both wells being plugged and abandoned.



The Ngueve-1 well was spudded on 3 November 2005 and intersected all of the
planned objectives before reaching a total depth of 2,830m.  Wireline logs
indicated that all the porous zones encountered by the borehole are water
bearing and the well was plugged and abandoned on 30 November 2005.



The second well, Henda-1, commenced on 5 December 2005 and was drilled to a
total depth of 1,539 metres.  Although the main objective was intersected, no
liquid hydrocarbons were encountered.  The well was therefore plugged and
abandoned on 15 December 2005.



Block 10 is a largely unexplored block covering some 4,800 sq km.  Although the
wells did not encounter commercial hydrocarbons, they provided key geological
and geophysical information that will be integrated with the 3D seismic data to
allow further evaluation of the prospectivity of Block 10 and the region.



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

'Although we believe the Faucon well is most unlikely to lead to a commercial
development, it significantly upgrades the prospectivity of Tullow's regional
position in Mauritania and Senegal, where further work is planned for 2006.
Similarly, while we are disappointed with the result of the Ngueve and Henda
wells, we remain committed to developing a long-term business in Angola. '

If you have any questions on this announcement please contact:


Tullow Oil plc         Citigate Dewe Rogerson              Murray Consultants
([phone])     ([phone])                  ([phone])
                       Martin Jackson                      Joe Murray
Tom Hickey
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 approximately 90
production and exploration licences in 16 countries and focuses on three core
areas: NW Europe, West Africa and South Asia.



Tullow's NW Europe 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.  Tullow operates 60% of its production from these areas
following the recent start-up of production from its Horne and Wren fields and
the acquisition of the Schooner and Ketch assets.

In Africa, Tullow has production and exploration in Gabon, Cote d'Ivoire, Congo
(Brazzaville) and Equatorial Guinea. Tullow also has exploration programmes in
Morocco, Mauritania, Senegal, Cameroon, Uganda and Angola.

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

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

                                      ENDS


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