Operational Update

Lansdowne Oil & Gas plc
09 May 2008


                                                                      9 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'.


Enquiries:

Lansdowne Oil & Gas plc
Stephen Boldy, CEO                               Tel: [phone]

Emmet Brown, Business Development                Tel: [phone]
Director

John East & Partners Limited
David Worlidge                                     Tel: [phone]



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.lansdowneoilandgas.com



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