Vietnam Discovery

SOCO International plc

('SOCO' or the 'Company')

 Vietnam Discovery

The Hoang Long Joint Operating Company, operator of Block 16-1 in the Cuu Long Basin offshore Vietnam, announces that the Te Giac Den appraisal well, TGD-2X, encountered hydrocarbons in a clastics sequence at approximately 4,450 metres measured depth. Drilled to appraise the "E" prospect discovery, TGD-2X reached total depth of 4,669 metres after penetrating the target hydrocarbon zone in the Oligocene "E" formation. The well logging is ongoing, however, drilling shows and early log interpretation indicate two main reservoir sand intervals. Approximately 40 metres will be tested after a 7" liner is set and cemented.

Testing is expected to take approximately three weeks. After the completion of testing there will be a further release with results and mapping a way forward.

1 September 2010

ENQUIRIES:

SOCO International plc

Roger Cagle, Deputy Chief Executive and Chief Financial Officer Tel: 020 7747 2000

Pelham Bell Pottinger

James Henderson Tel: 020 7861 3232

Evgeniy Chuikov Tel: 020 7861 3232

NOTES TO EDITORS:

SOCO is an international oil and gas exploration and production company, headquartered in London, traded on the London Stock Exchange and a constituent of the FTSE 250 Index. The Company has interests in Vietnam, Thailand, the Republic of Congo (Brazzaville), the Democratic Republic of Congo (Kinshasa) and Angola, with production operations in Vietnam and Thailand.

SOCO holds its interests in Vietnam, all in the Cuu Long Basin offshore, through its 80% owned subsidiary SOCO Vietnam Ltd. ('SOCO Vietnam') and through its 100% ownership of OPECO Inc. SOCO Vietnam holds a 25% working interest in Block 9-2, which is operated by the Hoan Vu Joint Operating Company and holds a 28.5% working interest in Block 16-1, which is operated by the Hoang Long Joint Operating Company. OPECO Inc. holds a 2% interest in Block 16-1.