French Guiana operational update

RNS Number : 5871C

Tullow Oil PLC

17 April 2013

News Release

17 April 2013 - Tullow Oil plc ("Tullow") provides an update on progress with the Priodontes-1 well, offshore French Guiana.

Tullow notes the announcement from its partner, Northern Petroleum plc issued at 11.40am today. This release was issued without prior notice from Northern Petroleum and without the approval of the operator or the joint venture partners.

Although the Priodontes well has not thus far encountered significant hydrocarbons, Tullow believes that this is due to a trap-specific issue and has no follow-on consequences for prospectivity elsewhere in the block. Tullow also notes that the shows encountered in the Bradypus fan, as described in Northern Petroleum's release, underline the presence of a working oil charge system.

This well is now being deepened to a proposed target depth of 6,483 metres to target additional formations after which Tullow will issue a further update.

FOR FURTHER INFORMATION CONTACT:

Tullow Oil plc

(London)
(+44 20 3249 9000)

Chris Perry (Investor Relations)

James Arnold (Investor Relations)

George Cazenove (Media Relations)

Citigate Dewe Rogerson

(London)
(+44 207 638 9571)
Martin Jackson

Jack Rich

Murray Consultants
(Dublin)

(+353 1 498 0300)
Joe Murray

Joe Heron

Notes to Editors

Tullow Oil plc

Tullow is a leading independent oil & gas, exploration and production group, quoted on the London, Irish and Ghanaian stock exchanges (symbol: TLW) and is a constituent of the FTSE 100 Index. The Group has interests in over 150 exploration and production licences across 25 countries which are managed as three regional business units: West & North Africa, South & East Africa and Europe, South America and Asia.

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