Development approval

Tullow Oil PLC
25 June 2001

The attached is the text of an announcement issued by Conoco today.

'Conoco wins UK Government approval for further natural gas development

ABERDEEN, Scotland, (June 25th, 2001). Conoco (U.K.) Limited and its
co-venturers GDF Britain Limited and Tullow Exploration Limited, have received
government consent to develop five natural gas discoveries adjacent to the
Caister and Murdoch fields in the southern area of the North Sea. It is
expected that the Stg£207million (US$294 million) CMS III project will achieve
first production of natural gas in the fourth quarter of 2002.

Conoco (U.K.) Limited is the British exploration and production affiliate of
Conoco (NYSE:COC.A) (NYSE:COC.B).

A potential 500 billion standard cubic feet of natural gas from the Hawksley,
McAdam, Murdoch K, Boulton H and Watt reservoirs will be produced through
subsea wellheads and flowlines to the adjacent Murdoch production platform.
From there, the existing Caister Murdoch System (CMS) pipeline will transport
it 115 miles to the Conoco-operated Theddlethorpe Gas Terminal in
Lincolnshire, England.

In order to facilitate development and simplify the ownership profile, Conoco
and its co-venturers have unitised their respective interests in the five
reservoirs into agreed holdings in a single project.

'The CMS III development demonstrates the co-operative approach of the UK
Government and the offshore oil and gas industry to cluster developments,
which will play an increasingly important role in the future of the country's
energy resources, ' said Dr. George Watkins, chairman and managing director of
Conoco (U.K.) Limited. 'Combining the latest subsea technology with
pre-existing facilities in the area allows Conoco and its partners to add
production from this important natural gas area cost effectively and with
reduced environmental impact. CMS III also reinforces Conoco's position as a
leading supplier of natural gas both in the UK and in Continental Europe.'

Mr. Brian Wilson, MP, Minister of State for Industry and Energy, said:- 'I
welcome this investment by Conoco and its partners in the southern North Sea,
made possible by the adoption of imaginative and collaborative working
practices. This is clearly the way forward and is further evidence that good
business opportunities are available in the UKCS. I particularly welcome the
activity boost this will give to the whole supplier network in the UK, which
will benefit from the contract awards in a number of areas, including
drilling, pipelay, specialist subsea equipment and fabrication.'

The CMS III project will consist of two main elements. These are:-


  * a Stg£149 million (US$212 million) satellites development, comprising
    subsea wellheads, flowlines and control systems required to produce
    natural gas back to the Murdoch platform for processing; and

  * a Stg£58 million (US$82 million) separate accommodation platform and an
    additional compression module to be located on CMS.

The enhanced compression facilities will cater for the CMS III production and
provide capacity for future natural gas developments in the area. Competitive
bids for the various contracts have been invited and the names of the
successful contractors will be announced soon.

The Conoco-operated Caister and Murdoch natural gas fields, which are located
115 miles north east of Lincolnshire, England, entered production in October
1993. The participating interests are Conoco (U.K.) Limited, (operator) 42.24
per cent; Consort Caister Limited 24.5 per cent; GDF Britain Limited 16.25 per
cent, and Tullow Exploration Limited 17.0 per cent.

Partners in the CMS III development are Conoco (U.K.) Limited (operator) 59.5
per cent; GDF Britain Limited 26.4 per cent, and Tullow Exploration Limited
14.1 per cent.

Conoco is a major, integrated energy company active in more than 40
countries.'



ENDS