Operational Update

6 June 2013

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

Operational Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to announce an update on its operations in Colombia and Paraguay

·; Platanillo-11 produced 1,500 BOPD over a controlled choke.

·; Alea-1R ST1 sidetrack is producing 700 bopd under controlled production

·; Platanillo Field production currently at 7,100 bopd

·; Total field production capacity estimated at 8,500 bopd

·; Platanillo-2 ST1 sidetrack commenced

·; Platanillo-12 spudded

·; Civil works expected to begin during June on the road construction to the northern platforms

·; 500 point gravity survey underway in Paraguay

Colombia - Platanillo Field

The Platanillo-11 well has been completed in the U sand and produced at a controlled rate of 1,500 BOPD with trace water in natural flow. The well has now been placed on production at approximately 1,100 BOPD.

The Latco-01 rig was skidded onto the next slot within the 5S location and spudded well Platanillo-12. Platanillo-12 is a directional well with the reservoir target located 1,770ft to the south east of the 5S location. The well is currently at 2,662ft.

Alea-1R ST1 has been placed on production, producing 700 BOPD at a controlled rate with 20% water cut, in line with expectations from the log interpretation.

The Serinco D-10 drilling rig has been moved over the Platanillo-2 well in the same location in order to side track it. Platanillo-2 will be sidetracked to a new position to the south of Pad A, a distance of approximately 3,400ft. The well is expected to take approximately 40 days to drill and log.

Logistical issues continue to constrain field production in Platanillo. However the Company's efforts to develop alternative options are proving successful and the net impact of the constraint has been significantly reduced. Current field production is approximately 7,100 BOPD against a calculated production potential of 8,500 BOPD. Amerisur continues to develop further export routes, at attractive pricing, to further support the development of the field.

Colombia - Fenix Block

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

Paraguay

A gravity survey has been initiated in the western blocks in Paraguay. This survey, of 500 high precision stations is being acquired in the prospection blocks in the Piriti-Pilar complex basin.

Dr. John Wardle, Chief Executive commented:

"We continue to be encouraged by successful results from the Platanillo field. We have now drilled 7 new wells and performed 2 sidetracks of legacy wells with a 100% success rate. This is a very strong endorsement of the geological model and bodes well for the wells to the north. With civil works on the northern road to Platform 3N commencing shortly I look forward to seeing further significant growth as we extend our reserves base beyond the strong results of Platanillo-1 side track. As we have already demonstrated, logistical issues can and will be addressed gradually to develop Platanillo to its full scale."

ENDS

Competent person: Technical information in this announcement has been reviewed by John Wardle Ph.D., the Company's Chief Executive. John Wardle has 29 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

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