Exercise of Options

5 February 2010

Amerisur Resources plc

Exercise of Options

Amerisur Resources plc, the oil and gas explorer and developer focused in South America, announces that on 4 February 2010, an employee of the Company exercised an option to acquire 500,000 ordinary shares at 3.00 pence. Application has been made for the shares to be admitted to AIM, with trading expected to commence on 9th February 2010 ('Admission'). Upon Admission, the shares will rank pari passu in all respects with the existing ordinary shares of the Company.

After admission of these new shares Amerisur Resources plc's capital consists of 830,385,301 ordinary shares of 0.1 pence each. Amerisur Resources plc does not hold any ordinary shares in Treasury.