Operational Update

14 May 2013

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

Operational Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, will hold its Annual General Meeting (AGM) today at 9:30 AM. At that meeting Giles Clarke, Chairman, and John Wardle, Chief Executive will provide the following summary on recent progress.

Colombia - Platanillo Block

·; Platanillo-11 encountered a 49.5 ft total net pay in the U sand and 17 ft net pay in the T sand.

·; Alea-1R sidetrack encountered a 40 ft total net pay in the U sand and 8.5 ft in the T sand.

·; Platanillo Field production currently at approximately 5,400 bopd, constrained by pipeline and export facility upgrade works.

·; Total field production capacity estimated at 7,500 bopd before the contribution of Platanillo-11 and Alea-1R ST1.

The well Platanillo-11, located on Platform 5 South (5S) has been drilled to a total depth of 8,733ft MD using the Latco-01 drilling rig. Platanillo-11 is a directional well, deviated approximately 1,697 ft south east of platform 5S. The well encountered an interval of 95 ft Gross, 49.5 ft net indicated pay in the U sand and 34 ft gross, 17 ft net in the T sand. As predicted by our geophysical model, the N sand was not well developed at this point. It is expected the well will be completed and placed on production during May.

The Latco-01 rig will be skidded onto the next slot within the 5S location and will spud well Platanillo-12. Platanillo-12 is a directional well whose reservoir target is located 1,837ft to the south west of the 5S location.

Alea-1, drilled in 1988 and re-entered in 2007 by Ecopetrol, was sidetracked to a location approximately 1,008ft to the north west of the original well location. This well, named Alea-1R ST1, encountered a gross pay interval of 85ft and 40ft net pay interval in the U sands. The T sand exhibited 18ft gross and 8.5ft net. It is expected that this well will also be completed and placed on production during May.

Post completion and testing of Alea-1R ST1, the Serinco D-10 drilling rig will be moved to the Platanillo-2 well in the same location in order to side track it. It is planned to re-enter and sidetrack that well to a structurally more favourable position for oil production.

Platanillo field production continues to be constrained by local export conditions but the Company continues to develop new alternatives for oil delivery, and expects those options to allow a continued growth in production over the coming months. As part of its efforts to enhance export capacity from the Platanillo, the Company has signed an agreement with the operator of the Rio Loro oil reception facility, Huila Colombia, to receive a minimum of 3,500BOPD from the Platanillo field. Current Platanillo Field production is running at approximately 5,400 bopd against an estimated capacity of 7,500 bopd before the contribution of Platanillo-11 and Alea-1R ST1.

Colombia - Fenix Block

Interpretation of the newly acquired 2D seismic data continues. The Company expects to drill a further exploration well in Fenix during the year.

Paraguay

A gravity survey has been initiated in the western blocks in Paraguay. Additionally the Company has performed geochemical analysis on cuttings from the Asuncion wells in the San Pedro block.

Giles Clarke, Chairman said:

"I am very pleased with the strong progress we have made over the last year. Our hard work in the fields has been rewarded with exceptional results, which we will continue to build upon. Our portfolio is both widening and deepening, creating along term, sustainable and very profitable business."

ENDS

A short presentation which will be given at the AGM will be available shortly after the AGM on the website www.amerisurresources.com.

Competent person: Technical information in this announcement has been reviewed by John Wardle Ph.D., the Company's Chief Executive. John Wardle has 28 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

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