AMER.L Regulatory News (AMER)

12th March 2012

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

Platanillo Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to announce that it has signed a contract for a drilling rig to perform its Platanillo drilling campaign.

The Serinco D10 1200HP drilling unit has been contracted for two firm wells with a continuing option to extend for further wells.

Serinco SA is an established Drilling and Workover rig provider and contractor which has performed various operations previously for the Company.

The D10 drilling unit recently drilled an 11,000ft well under contract to the Agencia Nacional de Hidrocarburos (ANH), and is currently located in Bogota and Tumaco. Following agreement of preventative maintenance and load out procedures, Serinco expects to begin mobilisation of the unit and its associated camp to the drilling location "Platform 9" in the southern part of the Platanillo field within the next week. Results from the first well are expected to be announced in May 2012.

The recently worked over Platanillo-2 well is now being tested with an Electrical Submersible Pump at higher rates than previously reported in natural flow. The Company is configuring the surface reception and treatment systems in order to efficiently handle and condition the flow for a Long Term Test of the N sand.

John Wardle, CEO of Amerisur, commented: "I am very pleased to have signed up Rig D10 and look forward to our contractor undertaking a rapid and efficient mobilisation to the drilling location. The start of our exciting drilling programme is most welcome; and given our success in the N sand of Platanillo-2 we have even more objectives to go for in the new wells. Testing of Platanillo-2 continues and we will update shareholders as soon as definitive data are known"

-Ends-

A presentation updated in February 2012 can be viewed on the Company 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 26 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

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