Development and New Business

Tullow Oil PLC
27 October 2004

Tullow Oil plc
27th October 2004


Tullow Oil plc  -  Horne & Wren Development and New Third Party Business

Tullow is pleased to announce the completion of a series of transactions
concerning its interest in the UK Horne and Wren fields. Having increased its
interest in the fields to 100%, Tullow subsequently divested 50% to GB Gas
Holdings Limited (an affiliate of Centrica plc).

Tullow obtained its initial 9% interest in these fields as part of an
acquisition from ARCO/BP in 2001 and has increased its interest to 50% through a
series of transactions with BP, Enterprise Oil Limited and Enterprise Oil
Exploration Limited (affiliates of Shell U.K. Limited) and GB Gas Holdings
Limited. The Horne and Wren fields, located in offshore UK Blocks 53/3c & 53/4b,
will be developed utilising an unmanned platform with export planned via the
Thames Offshore Infrastructure (Tullow 66.7%) and onshore Bacton Terminal
(Tullow 38.8%). Final DTI approval is imminent and first gas is anticipated in
the second quarter of 2005.

In addition, agreements have now been executed for the transportation,
processing and redelivery of production from the Arthur Field (70% Mobil North
Sea Limited, 30% EOG Resources United Kingdom Limited) via the Thames Offshore
Infrastructure and onshore Bacton Terminal. The Arthur field, located in Block
53/2, was discovered by Mobil North Sea Limited in November 2003 and first gas
production is currently anticipated by year end.

The combined production from the Horne & Wren and Arthur fields is expected to
increase the Thames Offshore Infrastructure throughput by over 150 mmscfd with
further increases anticipated.

Aidan Heavey, Tullow's Chief Executive commented: 'In the aftermath of the
Energy Africa deal, the Horne & Wren development and the Arthur third party
business represent a further important milestone for Tullow as it heralds a new
phase for the Thames-Bacton infrastructure.  This offers an opportunity to
prolong the useful life of these assets and their satellite fields for the
benefit of all the stakeholders.'

For Further Information Contact:

Tullow Oil plc ([phone])
Aidan Heavey
Paul McDade

Citigate Dewe Rogerson ([phone])
Alexandra Scrimgeour

Murray Consultants ([phone])
Joe Murray

Notes for Editors  -

'Tullow' where referred to in this release means Tullow Oil plc and/or its
subsidiaries, as appropriate

Tullow Oil plc is one of the leading Independent International Oil & Gas
Exploration and Production companies in Europe.  Tullow is quoted on the London
and Irish stock exchanges (symbol TLW) and is a member of the FTSE 250 Index.

Production and Development Assets

Tullow has interests in over ninety exploration and production licences spread
over three core areas:  UK North Sea, West Africa and South Asia. Tullow
recently completed the acquisition of Energy Africa, which takes the number of
countries in which Tullow is active to sixteen.

In the North Sea, Tullow's principal interests are in the CMS and the Thames/
Hewett group of licences and the Bacton onshore gas-processing terminal on the
Norfolk coast.

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

In South Asia, Tullow has production and exploration interests in Pakistan and
exploration activities in India and Bangladesh, where a three well drilling
programme is under way in Block 9.

For further information see www.tullowoil.com.


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