Change to Board of Directors

Tullow Oil PLC 6 April 2000 Tullow Oil plc Pat Plunkett to succeed Tom Toner as Chairman Board Changes Tullow Oil plc announces the following Board changes to support its plans to re-domicile as a UK Registered company. Pat Plunkett, currently a Non-Executive Director of the Company, succeeds Tom Toner as Chairman of Tullow with immediate effect. Pat was appointed to the Board of Tullow in 1998. He was previously Chairman and Managing Director of the stockbroking and corporate finance businesses of ABN AMRO in Ireland and has over thirty years' experience in the financial services industry. He was a Director of the Irish Stock Exchange Ltd between 1995 and 1998. He is currently a Director of a number of private companies. Matt Maher, Finance Director and Company Secretary is retiring from his executive duties with immediate effect but has agreed to remain as Company Secretary until the change of domicile becomes effective. Tom Hickey, Chartered Accountant, is joining Tullow as Finance Director in early May. Tom was previously an Associate Director of ABN AMRO Corporate Finance (Ireland) Ltd. In this role he advised a wide range of public and private companies in the areas of mergers and acquisitions, flotations and related transactions including Tullow's most recent Placing and Open offer in November 1999. Tom qualified with Arthur Andersen in Dublin where he worked on a number of assignments for public companies in the natural resources sector. Tom will be based at Tullow's London office. Duilio Ciriani, Executive Director and Dan O'Donohoe, Non- Executive Director are retiring from the board, both with immediate effect. Duilio will continue to retain his executive management responsibility for exploration. It is our intention to appoint additional UK-based Non- Executive Directors to ensure an appropriate balance within the Board following the re-domicile of the Company. Commenting on the announcement, Mr Aidan Heavey, Chief Executive of Tullow, said; 'We are delighted with the appointment of Pat Plunkett to the position of Chairman of Tullow. Pat has been closely involved with Tullow in an advisory capacity since 1994 and more recently as a Non-Executive Director. As we plan to re- domicile the Company to the UK where there is a wider investment audience and as Tullow continues to pursue an aggressive investment program in the exploration sector, Pat's experience and dynamism will be invaluable. We would like to take this opportunity to thank our outgoing Chairman, Tom Toner, who has made an enormous contribution to the evolution and development of the Company, since he joined in 1989. His vision and wise counsel have been central to the formulation and successful implementation of the Company's strategy during this period. We look forward to welcoming Tom Hickey to the Board of Tullow. We have worked with Tom Hickey for a number of years and have been impressed by the breadth of his financial capability and corporate expertise. I am confident he will make a very valuable contribution to the Group. Matt Maher has been with Tullow since 1987 and has been a key member of the Tullow management team. His knowledge and acumen have been of great assistance to the Board. We wish Matt well in his retirement and are pleased that he has agreed to remain as Company Secretary for a period to ensure a smooth transition to UK domicile. Both Duilio Ciriani and Dan O'Donohue have been Directors of Tullow for a number of years. Their professionalism and commitment to Tullow's interests throughout this period have been unwavering. As Tullow heads into an intensive period of exploration activity, Duilio's experience will remain critical to the Group and we are pleased that he will retain his executive responsibilities.' For further information please contact: Aidan Heavey Tel: 00 44 20 7976 2600 Chief Executive Graham Martin Tel: 00 44 20 7976 2600 Legal and Commercial Director Judith Parry/Simon Rothschild Tel: 00 44 20 7256 5756 Millham Communications

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Tullow Oil (TLW)
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