Drilling commences at Horse Hill

3 September 2014 Doriemus plc ("Doriemus" or the "Company") Drilling Commence at Horse Hill Doriemus Plc (AIM: DOR) is pleased to announce that drilling operations on theHorse Hill-1 well have now commenced. The Horse Hill-1 well is planned to be drilled to a Total Depth ("TD") of 2,646metres (8,680 feet) and is designed to test for a number of conventionalstacked oil targets in the Jurassic, as well as a deeper conventional gastarget in the Triassic. The operator, Horse Hill Developments Ltd ("HHDL"), is a special purposecompany with a 65% operating interest in the PEDL 137 license in the WealdBasin to the north of Gatwick Airport in Surrey. Doriemus has bindingagreements in place to own a direct 10% interest in HHDL. The participants in the Horse Hill Prospect are HHDL (65%) and MagellanPetroleum Corporation (35%). Donald Strang, the Company's Chairman, commented: "This is an exciting time for Doriemus. We are very pleased that drillingoperations are now underway on this exciting prospect. The next few weeks willbe a busy and interesting phase for this investment." Enquiries: Doriemus plc +44 (0) 20 7440 0640Donald Strang/Hamish Harris Cairn Financial Advisers LLP +44 (0) 20 7148 7900Nominated Adviser and BrokerJames Caithie/Jo Turner/Carolyn Sansom About Horse Hill: The 99.29 km2 (24,525 acre) Horse Hill Petroleum Exploration and DevelopmentLicence No. 137 (PEDL 137) ("Horse Hill") is located in Surrey, a few milesfrom Gatwick Airport The Horse Hill Prospect OOIP and OGIP and prospective resources, as previouslyannounced by the Company, are summarised in Table 1. Table 1: Horse Hill Prospect estimated OOIP, OGIP and Prospective Resources. Target Reservoir OOIP OOIP Prospective Resources Oil Upside Potential Mean (MMSTB) (MMSTB) Mean (MMSTB ) Upper Portland 116 57 17Sandstone Lower Portland 284 147 44Sandstone Corallian Sandstone 67 33 10 Greater Oolite 204 104 16Limestone Total Oil 671 341 87 Target Reservoir OGIP OGIP Prospective Resources Gas Upside Potential Mean (Bcf) (Bcf) Mean (Bcf) Triassic Sandstone 456 234 164 Glossary: MMSTB million stock barrels Bcf billion cubic feet OOIP Original Oil in Place OGIP Original Gas in Place Prospective Resource Prospective resources are estimated volumes associatedwith undiscovered accumulations. These represent quantities of petroleum whichare estimated, as of a given date, to be potentially recoverable from oil andgas deposits identified on the basis of indirect evidence but which have notyet been drilled. This class represents a higher risk than contingent resourcessince the risk of discovery is also added. For prospective resources to becomeclassified as contingent resources, hydrocarbons must be discovered, theaccumulations must be further evaluated and an estimate of quantities thatwould be recoverable under appropriate development projects prepared.