Holding in Company

Tullow Oil PLC 20 September 2000 Schedule 10 - Notification of Major Interests in Shares 1 Name of company: Tullow Oil plc 2 Name of shareholder having a major interest: Fidelity Investments 3 Please state whether notification indicates that it is in respect of holding of the shareholder named in 2 above or in respect of a non-beneficial interest or in the case of an individual holder if it is a holding of that person's spouse or children under the age of 18: As 2 above 4 Name of registered holder(s) and, if more than one holder, the number of shares held by each of them: Fidelity Investments 5 Number of shares/amount of stock acquired: N/A 6 Percentage of issued class: N/A 7 Number of shares/amount of stock disposed: N/A 8 Percentage of issued class: N/A 9 Class of security: Tullow Oil plc IR10p Ordinary Shares 10 Date of transaction: N/A 11 Date company informed: 15/09/00 12 Total holding following this notification: 16,816,100 13 Total percentage holding of issued class following this notification: 4.77% 14 Contact name for queries: Tom Hickey 15 Contact telephone number: (01) 2602611 16 Name of company official responsible for making notification: Tom Hickey 17 Date of notification: 20/09/00 Additional Information:

Companies

Tullow Oil (TLW)
UK 100