Amerisur Resources : Platanillo-25 Update

26 October 2017

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

Platanillo-25 Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to provide an update on Platanillo-25, the third well drilled on Pad 2N, the northern extension of the Platanillo Field.

Platanillo-25, the 20 well of the Platanillo drilling campaign, has been successfully side tracked to a total depth of 8,620 ft measured depth, on time and budget. Preliminary log interpretation, using Schlumberger logging-while-drilling tools, indicates the presence of a 22 ft net oil column in the U sand formation.

The side track located the production well further up dip, closer to the Platanillo 21 well, where better reservoir quality and additional pay thickness were found increasing the potential to deliver more sustainable production. 7' production casing has been successfully run and cemented and the Company expects to initiate commercial production from the U sand, to be evacuated through the OBA pipeline, in approximately 10 days.

The N sand, as expected, did not present net pay at this location but the M2 sand interpretation indicated a potential pay zone of 5 ft. In offset wells to the east of Platanillo and also in Ecuador, the M2 sand is a proven producing horizon. This result augurs well for the blocks to the north and east of Platanillo.

Once Platanillo-25 is completed, the drilling rig will move to drill Platanillo-27, a planned well to the north of Pad 2N. Platanillo-27 is targetinga bottom hole location to the north of Platanillo-22 in a structural position similar to Platanillo-21, with a U sand structural target.

John Wardle, Chief Executive Officer, commented:

'This is a further good result on Pad 2N. I look forward to updating shareholders on the production performance of the well.'

ENDS

Enquiries:

Competent person

Technical information in this announcement has been reviewed by John Wardle Ph.D., the Company's Chief Executive. John Wardle has 31 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

Inside Information

This announcement contains inside information as defined in EU Regulation No. 596/2014 and is in accordance with the Company's obligations under Article 17 of that Regulation.

Important notice

Forward looking statements and dates referenced in this announcement, in relation to Amerisur's production, development and exploration assets, are estimates and subject to change. Oil and gas operations are subject to varying inputs that may impact timing, including, inter alia, permitting; environmental regulation; changes to regulators and regulation; third party manufacturers and service providers, social issues and the weather. The Company's estimates of timing for forward looking operations are based on the best information it has to hand at the time, however these timings may change with little or no notice to the Company. The Company will update the market as and when it becomes aware of a material change to any of the operations or timings referenced in this announcement.

Notes to editors

Amerisur Resources is an independent full-cycle oil and gas company focused on South America, with assets in Colombia and Paraguay and production from the Platanillo field in southern Colombia. In 2016 Amerisur successfully built and is 100% owner of the strategic OBA oil transfer line into Ecuador.

In Colombia, the Company is operator and has a 100% working interest in the Platanillo block which includes the Platanillo field, which is currently producing circa 6,400 BOPD. The Company has a strong position in the Putumayo basin and has a cluster of near term activity assets around the OBA export line including the Platanillo block, Put-8, Put-12 and Coati. Additionally, the Company holds a 100% working interest in contract Put-9, 100% of Tacacho and 100% of Terecay acquired from Talisman and Pacific. These acquisitions have now been approved by ANH. It has a diverse portfolio of longer term exploration assets.

www.amerisurresources.com