AMER.L Regulatory News (AMER)

3 October 2012

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

Platanillo-5 Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to announce an update on the well Platanillo-5 in the Platanillo Field, Colombia, the third well of a planned eight well drilling campaign.

Platanillo-5 was drilled as a directional well from the Platform 9 location to a bottom hole location approximately 1,420ft north of Platanillo-3. After analysis of the electric logs Schlumberger has estimated that the Platanillo-5 well encountered an interval of 99ft gross, 79ft net oil bearing pay in the U sands of the Villeta formation. The Company is currently running a completion assembly and intends to perforate the upper 30ft of indicated net pay.

Two further zones within the Villeta may also contain potential pay and are under evaluation.

Platanillo-5 will be flow tested on commercial production in the next few days via the test separator installed on Platform 9.

The Company plans to rig down and move the Serinco Rig D-10 and drill Platanillo-9 (so numbered due to the order in which wells were permitted with the Ministry of Mines and Energy), the fourth well of the current programme from the same location (Platform 9), deviating the well to an offset of approximately 1,550ft west of Platanillo-3.

John Wardle, Chief Executive, commented: "I'm very pleased with the well results to date and look forward to updating shareholders on flow data very shortly."

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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