Fastnet Oil & Gas 3D Seismic and Farm-Out

19 March 2013

Fastnet Oil & Gas plc

("Fastnet" or the "Company")

FASTNET ANNOUNCES SIGNING OF CONTRACT FOR 3D SEISMIC ACQUISITION IN THE CELTIC SEA AND COMMENCEMENT OF FARM-OUT PROCESS

Highlights

§ Seismic contract with CGG executed to acquire 1,710 km2 of 3D seismic - the largest ever 3D seismic programme in the Celtic Sea

§ Acquisition using the SR/V Vantage vessel ("SR/V Vantage") to commence in mid-April 2013: approximate duration of programme is 50 days

§ Value of contract award is up to US$18 million, depending on weather and standby downtime

§ 3D seismic should de-risk and mature prospective structures for early drilling

§ Farm-out process over Celtic Sea assets has been initiated and initial expressions of interest received; intention for potential farminees to meet an appropriate portion of the 3D costs

Further to the announcement of 18 February 2013, Fastnet (AIM: FAST, ESM: FOI), the listed E&P company focused on near term exploration acreage in the Celtic Sea and Morocco, is pleased to announce that it has executed a seismic contract with CGG to acquire, using the SR/V Vantage, 1,710 sq. km. of 3D seismic in the Celtic Sea beginning in mid-April 2013. The total value of the programme is up to US$18 million. The programme is likely to last for approximately 50 days, depending on weather and standby time.

510 Km2 of 3D seismic will first be acquired over the "Deep Kinsale Prospect" beneath the producing Kinsale Head gas field. Seismic operations will include an undershoot of the Kinsale Alpha and Bravo platforms, which are protected by a 500 meter safety exclusion zone. This will require, under the existing seismic contract, mobilising a second 3D seismic vessel for a short period of time during the acquisition of the data by the SR/V Vantage. The geological target will be the same reservoir section that has been successfully tested at Barryroe by the 48/24-10z appraisal well.

1,200 sq. km. of 3D seismic will then be acquired over Licensing Option 12/3 ("Mizzen") and adjoining areas. Several large structures have been identified on existing 2D seismic data that are prospective for Triassic, Jurassic and Lower Cretaceous reservoir targets.

The 3D seismic surveys are the largest ever to be undertaken in the Celtic Sea.

There is flexibility to accommodate up to two additional contingent 3D seismic surveys over other acreage subject to the level of interest from potential farminees.

A farm-out process has commenced and initial expressions of interest have already been received from a range of multi-nationals, mid-caps and small-caps.

Paul Griffiths, Managing Director of Fastnet, said:

"This is the first large-scale 3D seismic programme to be acquired in this part of offshore Ireland. Whilst we are targeting proven hydrocarbon systems around the Kinsale and Barryroe fields, we are also evaluating a prospective part of the Celtic Sea Basin covering approximately 4,250 km2 that has seen only one well drilled in 1975 by Esso, which encountered oil shows. 3D seismic is the first step to creating material, "drill ready" prospects.

"Even at this very early stage in the farm-out process we are very encouraged by the level of interest being shown by a broad spectrum of companies and, despite our cash position of c.US$35 million, it is our intention that any partner would pay an appropriate proportion of the costs of this large seismic survey."

Ends

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Notes to editors

Fastnet Oil & Gas plc is an independent oil and gas exploration company that focuses on identifying early stage exploration and appraisal opportunities in Offshore Ireland and Africa. It is quoted on the AIM market of the London Stock Exchange and the Enterprise Securities Market (ESM) of the Irish Stock Exchange. Fastnet's aim is to assemble a portfolio of high impact conventional oil and gas assets that will deliver sustainable growth and value for the Company. Its immediate focus is on implementing its Offshore Ireland and Africa strategies where it has been awarded four offshore licensing options in the Celtic Sea (Molly Malone Basin, Shanagarry, 49/13 and Mizzen Basin) and acquired a material interest in the highly prospective Foum Assaka permit Offshore Morocco. In addition, Fastnet will continue to pursue new conventional oil and gas opportunities in Africa where the Directors and Advisory Board also have extensive knowledge, contacts and experience of creating value.

A picture of the SR/V Vantage seismic vessel is available on the announcement that has been uploaded to the Company's website.