AMER.L Regulatory News (AMER)

24th November 2010

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

Operations Update

Amerisur Resources Plc, the oil and gas producer and explorer focused on South America, announces today an update on operations in the Platanillo contract in Colombia.

Despite unprecedented weather conditions in Colombia as a whole and in the Putumayo area in particular, which has led to the President declaring a state of National Calamity, production operations have continued without interruptions over the last few months. Daily oil production has averaged 573 BOPD over the last 15 days.

The 3D3C seismic programme has experienced a slight delay in the face of these conditions, as the Platanillo area has been affected by flooding which has complicated access in both the southern area near the Rio Putumayo and the central area, around the Rio Pinuna Blanco.

It is now expected that the recording of data in the southern section of the data volume will be completed during December, with well locations identified in time for drilling during the first quarter of 2011, so long as ground conditions allow the required civil works to go ahead.

John Wardle, CEO, said:

"The wet season this year in Colombia has been longer and more severe than any since records began. That we have maintained the continuous production and export of produced oil from Platanillo and Fenix is a tribute to our operational team. The progress on the 3D3C programme has been excellent given the exceptional conditions and I look forward to receiving the first part of the data during December so that we can initiate our exciting drilling programme during 2011."

Competent person: Technical information in this announcement has been reviewed by John Wardle Ph.D., the Company's Chief Executive. John Wardle has 25 years' experience in the industry, having worked for BP, Britoil, Emerald Energy and Pebercan, and is a trained drilling engineer.

ENQUIRIES:

Notes to editors

The Platanillo contract is a commercial area held with the Agencia Nacional de Hidrocarburos located in the Putumayo basin of southern Colombia, near the border with Ecuador. The Company has a 100% interest in this area. As a commercial area, the Platanillo block has no exploration commitments. The exploitation period is 24 years, with the facility to extend to the end of field economic life should the Company wish to do so. The Exploitation Area was recently extended to the national boundary to the south of the previous block limit.