UK Oil & Gas PLC

("UKOG" or the "Company")

Horse Hill Oil Field: HH-2z Horizontal Drilling Completed

UK Oil & Gas PLC (London AIM: UKOG) is pleased to announce the successful completion of its Horse Hill-2z ("HH-2z") Portland horizontal drilling campaign (UKOG 85.635% net controlling interest). A total of approximately 2,500 ft of horizontal trajectory was drilled wholly within the Portland reservoir's most oil productive zone or "sweet spot", around 70 times greater exposure to the sweet-spot than seen in the HH-1 Portland vertical discovery well. The campaign's key technical objectives have now all been successfully delivered.

The significantly increased exposure to the sweet-spot within HH-2z, the first horizontal well in the field's Portland oil pool, is the prime technical enabler for HH-2z to be capable of delivering significantly greater flow rates than those seen in the HH-1 vertical well.

The good, clean horizontal trajectory, together with the continued indications of possible improved reservoir quality and significantly lower pressure-depletion than expected, led the Company to decide that there was little technical or economic benefit in pursuing drilling to the maximum planned c. 3,000 ft horizontal trajectory.

Following yesterday's completion of a comprehensive electric logging programme, HH-2z is now being prepared for an extensive extended well test ("EWT") programme, expected to commence in the coming weeks. The EWT, which will include the use of a British designed high-capacity/high-rate downhole electric pump or "ESP", is planned over a minimum 90-day flow period, following which HH-2z and HH-1 will be retained and converted into long-term oil production wells.

Oil production from the HH-1 EWT has continued throughout HH-2/2z drilling and will also continue in parallel with the HH-2z EWT. Total HH-1 test production now stands at over 77,200 barrels.

Analysis and integration of the 240 ft of core, cuttings and electric log data suites acquired in both the HH-2 pilot and HH-2z horizontal continues. Any impactful results will be reported in due course.

UKOG holds a controlling 85.635% interest in the Horse Hill oil field and surrounding highly prospective PEDL137 and PEDL246 licences, which are operated by UKOG's subsidiary company, Horse Hill Developments Ltd.

Stephen Sanderson, UKOG's Chief Executive, commented:

"We are delighted to have safely and successfully delivered a significant 2,500 ft of horizontal section within the Portland reservoir's sweet-spot, the prime 35 ft zone containing the reservoir's most oil productive sandstones.

The significant horizontal trajectory, combined with the continued positive indications of increased reservoir quality and lower pressure-depletion, effectively negated any technical or economic need to attain the maximum planned c. 3,000 ft horizontal section. As a result, HH-2z remains optimally placed to be able to deliver its goal of significantly higher flow rates than the highly productive HH-1 vertical discovery.

We now look forward to the imminent flow test campaign, a key step towards delivering significant long-term production at Horse Hill."

Qualified Person's Statement

Matt Cartwright, UKOG's Commercial Director, who has over 36 years of relevant experience in the global oil industry, has approved the information contained in this announcement. Mr Cartwright is a Chartered Engineer and member of the Society of Petroleum Engineers.

For further information, please contact:

UK Oil & Gas PLC

Stephen Sanderson / Kiran Morzaria Tel: 01483 900582

WH Ireland Ltd (Nominated Adviser and Broker)

James Joyce / James Sinclair-Ford Tel: 020 7220 1666

Cenkos Securities PLC (Joint Broker)

Joe Nally / Neil McDonald Tel: 0207 397 8919

Novum Securities (Joint Broker)

John Bellis Tel: 020 7399 9400

Public Relations

Brian Alexander Tel: 01483 900582

Glossary

coring	a drilling technique that involves using a doughnut-shaped drilling bit to capture or "cut" a continuous cylinder-shaped sample of in-situ rock. The core is captured in a steel pipe or "core barrel" above the bit. Core is normally cut in 30 feet lengths, or multiples of 30 feet, and with a diameter of 3-4.5 inches. Core is taken in petroleum reservoir rocks for detailed laboratory analyses of geological, geochemical petrophysical and geomechanical properties
horizontal well	a well that during drilling is steered so as to follow and remain within a particular geological stratum or reservoir unit having a trajectory that runs approximately parallel to the top and or base of the target horizon
oil field	an accumulation, pool or group of pools of oil in the subsurface that produces oil to surface
well test	or flow test involves testing a well by flowing hydrocarbons to surface, typically through a test separator; key measured parameters are oil and gas flow rates, downhole pressure and surface pressure. The overall objective is to identify the well's capacity to produce hydrocarbons at a commercial flow rate and volumes.

UKOG Licence Interests

The Company has interests in the following UK licences:

Asset	Licence	UKOG Interest	Licence Holder	Operator	Area (km²)	Status
Avington ¹	PEDL070	5%	UKOG (GB) Limited	IGas Energy Plc	18.3	Field currently temporarily shut in
Broadford Bridge/Loxley/Godley Bridge ^{2, 3, 8}	PEDL234	100%	UKOG (234) Ltd ⁴	UKOG (234) Ltd ⁴	300.0	BB-1/1z oil discovery, Loxley-1 gas appraisal well planning application submitted
A24 ³	PEDL143	67.5%	UKOG	UKOG ⁷	91.8	Finalising new site selection to drill Portland and Kimmeridge prospects
Horndean ¹	PL211	10%	UKOG (GB) Limited	IGas Energy Plc	27.3	Field in stable production
Horse Hill ⁵	PEDL137	85.635%	Horse Hill Developments Ltd ^⁶	Horse Hill Developments Ltd ^⁶	99.3	Production tests ongoing, HH-2/2z drilling completed
Horse Hill ⁵	PEDL246	85.635%	Horse Hill Developments Ltd ^⁶	Horse Hill Developments Ltd ^⁶	43.6	As above
Isle of Wight (Onshore) ^{2, 3}	PEDL331	95%	UKOG	UKOG	200.0	Preparing planning submission for Arreton-3 oil appraisal well and Arreton South exploration well
Markwells Wood	PEDL126	100%	UKOG (GB) Limited	UKOG (GB) Limited	11.2	MW-1 P&A

Notes:

1. Oil field currently in stable production.

2. Oil discovery pending development and/or appraisal drilling.

3. Exploration asset with drillable prospects and leads.

4. Contains the Broadford Bridge-1/1z Kimmeridge oil discovery, the eastern extension of the Godley Bridge Portland gas discovery, plus further undrilled Kimmeridge exploration prospects.

5. Portland and Kimmeridge Oil field with productive and commercially viable zones, EWT ongoing, production planning consent granted in September 2019, appraisal/development drilling campaign completed. Long term production start expected late 2019.

6. UKOG has a direct 77.9% interest in HHDL, which has a 65% interest in PEDL137 and PEDL246.

7. OGA consent received for the transfer of operatorship from Europa to UKOG

8. Gas discovery pending appraisal drilling and development with underlying Kimmeridge potential

The information contained within this announcement is deemed by the Company to constitute inside information under the Market Abuse Regulation (EU) No. 596/2014