09 May 2008

Lansdowne Oil & Gas plc (“Lansdowne” or “the Company”)

Operational Update Celtic Sea seismic survey completed

Lansdowne Oil & Gas plc, the Dublin-based exploration company, is pleased to announce the successful completion of its 2D seismic acquisition programme on Licence 5/08, in the Celtic Sea, offshore Ireland.

The Norwegian based company, Wavefield Inseis ASA, carried out the survey on behalf of Lansdowne using the M/V Malene Ostervold. The survey was completed ahead of schedule and under budget. A total of 489 kms of 2D seismic survey was acquired over two large structures, Amergin and Eremon that were identified on 1986 vintage seismic data. Amergin has been independently verified as having best case potentially recoverable prospective resources of 63 million barrels of oil equivalent (“MMBOE”).

Standard Exploration Licence 5/08 was awarded last month to Lansdowne’s recently acquired wholly-owned subsidiary Milesian Oil & Gas Limited (“Milesian”). Standard Exploration Licence 5/08 covers an area of 449 sq kms over parts of blocks 47/25, 48/21, and 48/22. The blocks are located 30 kms from the coastline, in water depths of approximately 100 metres.

Standard Exploration Licence 5/08 is valid for a period of six years (in two three year phases) during which Milesian is required to drill an exploration well and to complete the acquisition of 300 kms of new seismic data within the first three year phase. The acquisition of the seismic data has fulfilled the latter obligation. Under the terms of the licence, on 31 March 2011 Milesian is required to surrender 50 per cent. of the licence area.

Steve Boldy, Chief Executive of Lansdowne, commented:

Fortunately, good weather offshore enabled us to acquire the seismic data efficiently and cost effectively. The data will be processed over the coming months and integrated into our mapping which should give us a drilling target to best test the Jurassic oil potential in the area.


Lansdowne Oil & Gas plc
Chris Moar, Company Secretary01224 748 480
John East & Partners Limited
David Worlidge / Simon Clements020 7628 2200
College Hill - London
Nick Elwes020 7457 20200

Lansdowne Oil and Gas plc
Britannia House
Endeavour Drive
Arnhall Business Park
AB32 6UF
Tel: +44 (0)1224 748480
Fax: +44 (0)1224 748481
Email: info@lansdowneoilandgas.com
Web: www.lansdowneoilandgas.com

Notes to Editors:

Lansdowne Oil & Gas plc is an independent oil and gas exploration company listed on the AIM market in London with its operations focused on the Irish offshore North Celtic Sea basin. Its operating headquarters is in Dublin.

The Company was founded in December 2005 and admitted to AIM in April 2006 having acquired from Ramco Energy plc its portfolio of Irish exploration and appraisal assets that flank the Kinsale Head gas field and its infrastructure. The Company recently significantly expanded its North Celtic Sea portfolio through the acquisition of Milesian Oil & Gas Limited in December 2007 with its identified exploration prospects for Jurassic oil and gas.

Following the acquisition and interpretation of this new seismic further consideration may become payable to the Milesian vendor shareholders.

An updated Independent Technical Report relating to Milesian’s acreage will be commissioned following the conclusion of the seismic programme. If that report confirms best case potentially recoverable prospective resources of at least 63 MMBOE then a further 2,333,419 new shares in Lansdowne will be issued to the Milesian vendor shareholders.

Additionally for each 1 MMBOE of best case potentially recoverable prospective resources above 63 MMBOE, but capped at a total of 155 MMBOE a further 62,790 new Lansdowne shares will be issued to the Milesian vendor shareholders. Therefore a maximum of 8,110,099 new Lansdowne shares may become issuable where the best case potentially recoverable prospective resources reach 155 MMBOE.

Further information on Lansdowne is available at Lansdowne’s website at www.www.lansdowneoilandgas.com