AMER.L Regulatory News (AMER)

24 January 2013

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

Colombia 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.

·; Platanillo-6 well was completed and produced 1,550 bopd in a controlled production test

·; Platanillo-6 encountered 85ft gross, 51 ft net pay in U sand, 10ft net pay in T sand

·; Platanillo Field production currently at 4,600 bopd, constrained by pipeline and export facility upgrade works

·; Total field production capacity estimated at 5,400 bopd

·; Platanillo-10 well spudded and currently at 1,530ft

·; Platanillo-1 ST1 sidetrack to commence shortly

Platanillo Update

The well Platanillo-6, the fifth well of a planned 8 well drilling programme and located on Platform 5 South (5S) has been drilled to a total depth of 8,608ft MD using the recently contracted Latco-01 drilling rig and has been completed for production. Platanillo-6 is a directional well, deviated approximately 1,450ft south east of platform 5S. The well encountered an interval of 85ft Gross, 51ft net indicated pay in the U sand and 13ft gross, 10ft net in the T sand. As predicted by our geophysical model, the N sand was not well developed at this point. An interval of 34ft in the U sand was perforated with tubing conveyed guns and the well flowed 1,550 barrels of 30.8° API oil per day over a controlled choke with trace water. The well has now been placed on controlled production at approximately 1,150 bopd.

The Latco-01 rig was skidded onto the next slot within the 5S location and has spudded well Platanillo-10. That well is currently drilling ahead at 1,530ft. Platanillo-10 is a directional well whose reservoir target is located 1,850ft to the north east of the 5S location..

Serinco rig D-10 has been moved to the location of well Platanillo-1, located on Platform 1N, 2.5km north of the wells Alea-1R and Platanillo-2. Platanillo-1, drilled in 2007, was never tested by the previous operator, ECOPETROL; however Amerisur's log analysis indicates that an oil column exists in the U sand at this location. The rig is currently being inspected and tested before beginning the sidetrack in the next few days. Platanillo-1 will be re-entered with the objective of drilling a deviated well to a location approximately 2,500ft to the east. The objective of the sidetrack is to further delineate the oil columns in the Platanillo reservoirs and potentially to provide a water injection facility for the field. Depending on the results from this well, named Platanillo-1 ST1, further wells may be drilled from Platform 1N.

As previously reported, the maintenance and upgrade programme being performed by ECOPETROL at its Orito facilities and on the OTA pipeline has impacted the Company`s ability to deliver oil production to that point of sale. Whilst Amerisur continues to develop additional delivery options, the constraint on production is expected to last approximately a further 4 weeks.

Fenix Update

The Company is pleased to report that the 54.8km 2D seismic acquisition programme in the Fenix block has been successfully completed and the data is currently being processed with results available for interpretation during February 2013.

Dr. John Wardle, Chief Executive commented: "This is another strong result, underlining the long term potential of the Platanillo field. With 2 rigs shortly working in unison I look forward to further exciting news. The constraints on production are likely to be short term and we are meanwhile developing a suite of alternatives to ensure future production growth is unaffected"

ENDS

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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