Reserves Update

29 March 2016

Amerisur Resources Plc ("Amerisur" or the "Company")

Reserves Update

"1P reserves of 15.2MMBO, 2P reserves of 23.7MMBO"

Amerisur Resources Plc ("Amerisur" or the "Company"), the oil and gas producer and explorer focused on South America (LSE: AMER), is pleased to announce an update to the certified reserves for its production assets in Colombia.

Following receipt of an independent reserves report for the Platanillo field as at 31 December 2015 undertaken by Petrotech Engineering Ltd, using the standards set by the Oil and Gas Reserves Committee of the Society of Petroleum Engineers, certified 1P (Proven) gross field reserves were 15.2 million barrels of oil ("MMBO") (2014: 16.2 MMBO) after production of 1.62 MMBO during 2015 and 2P (Proven and Probable) gross field reserves were 23.7 MMBO (2014: 24.55 MMBO).

Production during 2015 was 1.62 MMBO; hence current 1P reserves represent a small increase from year end 2014. This technical increase of the Expected Ultimate Recovery ("EUR") (a forward looking model which assumes a decline factor and projects the volume of oil which will ultimately be recovered) takes account of the successful Long Term Test of the T sands from Platanillo-20 undertaken during the year. In addition, the reserves have benefitted from an increase in the recovery rates per well following the Schlumberger integrated study and the results of the successful treatments of well Platanillo-14 and Platanillo-20. During the period there were no reserve additions from the drilling of new wells as no new development or appraisal wells were drilled on the Platanillo field following the Board's responsible decision in Q1 2015 to shut in unprofitable production and only spend in risked capex what the production generated in cash flow.

The Board expects an increase in reserves once production increases again from currently shut in pads, which will happen gradually following the commissioning of the OBA pipeline which is due in April 2016 and once the much reduced opex per barrel comes through from production going through the OBA pipeline. In addition, the additional drilling activity planned on Platanillo in 2016, including two infill wells and up to two wells from the northern pad 2N, which seek to extend the field limits, together with the drilling of wells on Put-8 and Coati and the Long Term Test of the Temblon discovery to the south of the Coati block, should result in an increase in both 1P and 2P reserves. It is worth noting that six months of Long Term Testing is required before resources can be categorised as reserves.

An update of the resources report is currently under preparation by Petrotech Engineering Ltd in relation to all Amerisur´s portfolio, including the Put-8, Andaquies and Coati blocks which were acquired after the year end. It is expected to publish the results of that study in in the weeks ahead.

John Wardle, CEO of Amerisur Resources said:

"When taking account of the 1.62 MMBO we produced last year, I am pleased reserves have in effect increased this year following the Long Term Test of the T sand in Platanillo-20, and the Schlumberger integrated study, despite no additional drilling on the Platanillo field. With our accelerated activity plan for 2016 in which will see drilling on Platanillo, Put-8, Coati and the Long Term Test of the Temblon discovery in Coati South, we should see positive reserves momentum in 2016. Indeed the Jaguarete well, which is due to spud in April in Paraguay, on success, has the potential to substantially increase the company's reserves and resources base." 

Competent person: Technical information in this announcement has been reviewed by John Wardle Ph.D., the Company's Chief Executive. John Wardle has 31 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

Petrotech Engineering Ltd is an independent reserves assessor and conducts independent reserves reports for companies such as Canacol Energy Ltd, Pacific Rubiales and Petro America Oil Corp amongst others.

Ends

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Notes to Editors

Amerisur Resources is an independent full-cycle oil and gas company focused on South America, with assets in Colombia and Paraguay and production from the Platanillo field in southern Colombia. Amerisur's strategy is to acquire, explore and develop large acreage positions in major under explored basins located in South America. The Company's distinctive approach has been to own 100% of its assets at early stages in order to have full control over the fields' development. That requirement is now being relaxed as a sound production baseline has been established and in response to the widening opportunity set to which the Company has access.

In Colombia, the Company is operator and has a 100% working interest in the Platanillo block which includes the Platanillo field which is currently producing circa 4,350 BOPD. The 11,341 hectare block is located in the Putumayo Basin. The Company has a 60% working interest and operatorship in block Put-12, a 55,000 hectare block which is adjacent to Platanillo and shares its geology and a 50% working interest in Put-30 a 38,514 hectare block, approximately 55km to the north of the Company's 100% owned Platanillo field. In addition, the Company has a 30% working interest in the CPO-5 contract, located in the Llanos basin and a 49.5% working interest in the Tacacho contract, located in the Caguan-Putumayo basin. The Company has recently acquired 50% working interest in PUT-8 Block adjacent to the west of Platanillo, a 100% working interest and operatorship in the Coati Evaluation Area (Temblon Field) within the Coati Block located in the South West of the Putumayo basin and a 100% working interest and operatorship in the Andaquies Block located in the north east of the Putumayo basin.

In Paraguay, Amerisur is the largest acreage holder in the country, with 5.2 million hectares covering five 100% owned oil and gas permits in the Paraguayan part of the Chaco and Parana Basins.

John Wardle is CEO of Amerisur, having worked in Colombia since 1994, first for BP Exploration and subsequently for Emerald Energy. The Company is chaired by Giles Clarke and is listed on the AIM Market of the London Stock Exchange.

About Petrotech Engineering Ltd

Petrotech Engineering Ltd. is an independent oil and gas reserve evaluation firm located in Burnaby, British Columbia, Canada. John Yu is a professional Petroleum Engineer with over 40 years of experience in Domestic and International Oil and Gas. He attended the University of Alberta and graduated with a Bachelor of Science in Metallurgical Engineering in 1974. He is a registered Professional Engineer in the Province of British Columbia. Since May of 1981 he has been a Petroleum Engineering Consultant and President of Petrotech Engineering Ltd. of Burnaby, B. C.

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