Platanillo-9 Update - Replacement

Correction to RNS 9051P: in the Company's announcement dated 31 October 2012 the current depth of Platanillo-9 was said to be 5,490ft instead of 5,725ft. The full text of the announcement follows, including the correct figure at the time it was released. Since the announcement was released, further drilling has meant that the current depth of the well is 6,032ft.

31 October 2012

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

Platanillo-9 Update

·; Platanillo-9 currently at 5,725ft

·; Platanillo field controlled production approximately 3,800 BOPD

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to announce an update on the well Platanillo-9 in the Platanillo Field, Colombia, the fourth of a planned eight well drilling campaign.

Platanillo-9 is being drilled directionally to a reservoir target approximately 1,525ft west of the bottom hole location of Platanillo-3. The well is currently at a depth of 5,725ft, having successfully set and cemented 9.5/8". Total depth of the well will be approximately 8,650ft. The Company expects log data from this well and to update the market by the middle of November.

The wells in the Platanillo field continue to produce commercially at a controlled rate of approximately 3,800 BOPD. The Company expects to exit 2012 with a production rate of 5,000 BOPD.

After Platanillo-9 is completed and placed on production the Company intends to shift drilling operations to Platform 5 (the second new drilling location in the south of the field), for which civil works are already well advanced and will be ready by the time Platanillo-9 is completed. That platform has been redesigned to incorporate 4 drilling cellars as at Platform 9. Amerisur is also completing preparations to begin work on the northern platforms as well as further platform located between the Alea location and Platform 5.

John Wardle, Chief Executive Officer, commented:

"Drilling is progressing to plan and I look forward to updating shareholders on the results from Platanillo-9 and on our exciting development programme as it evolves."

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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