Platanillo-27 Update

14 December 2017

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

 Platanillo-27 Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, is pleased to provide an update on Platanillo-27, the fourth well on Pad 2N, the northern extension of the Platanillo Field.

Platanillo-27, the 21st well of the Platanillo drilling campaign, has been successfully drilled as a medium deviation directional well, to a total depth of 9,600ft measured depth, on time and budget. The well is the fourth successful sidetrack to have been drilled by the Company on the northern extension of the Platanillo Field.

The well was aimed at the crest of the northern part of the mapped structure and log interpretation indicates the presence of 12 ft net pay in the U sand formation and a 9ft net pay in the T sand formation using Schlumberger logging-while-drilling tools. The N sand was not a target at this location. The well also intersected the M2 sand and A limestone and log data is being evaluated to determine their potential as pay zones.

The 7" production casing has been successfully run and cemented and the Company expects to initiate commercial production from the U sand.

John Wardle, Chief Executive Officer, commented:

"I am pleased to announce another good result on Pad 2N, the fourth successful well of our new Platanillo campaign. 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 producing Platanillo Field and holds a 30% non-operated working interest in the CPO-5 block in the Colombian Llanos basin. Group production from the Platanillo Field and CPO-5 is currently in excess of 7,000 bopd. Additionally 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. Also, the Company holds a 100% working interest in contract Put-9, 100% of Tacacho and 100% of Terecay acquired from Talisman and Pacific. It has a diverse portfolio of longer term exploration assets.

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.

www.amerisurresources.com