Letter of Intent signed

5 February 2018 

Rockhopper Exploration plc

("Rockhopper" or the "Company")

Letter of Intent signed with Diamond Offshore Drilling

Rockhopper Exploration plc (AIM: RKH), the oil and gas company with key interests in the North Falkland Basin and the Greater Mediterranean region, is pleased to provide the following update relating to Sea Lion Phase 1, in the North Falkland Basin (RKH 40% working interest).

Rockhopper announces that a Letter of Intent ("LOI") has been entered into with Diamond Offshore Drilling ("Diamond") for the provision of a suitable drilling unit for the Sea Lion Phase 1 development. The LOI grants a period of exclusivity until 31 December 2018 during which time the joint venture will negotiate binding documentation based on agreed principles for the provision of the drilling unit and vendor financing.

Samuel Moody, Chief Executive of Rockhopper, commented:

"2018 has already seen material progress made on our work in moving Sea Lion closer to sanction. We are delighted to have been able to enter into this LOI with Diamond with whom we enjoyed a fantastically successful, safe and cost-effective drilling campaign in the Falklands during 2010 and 2011. We believe that teaming up with Diamond is a significant step in our continued progress towards sanction with our partner Premier Oil. Having already signed LOIs for the provision of well services and logistical support, focus now moves to the sub-sea equipment suppliers where we hope to make progress during the remainder of Q1 as we continue discussions on the senior debt element of the financing plan."

Enquiries:

Rockhopper Exploration plc

Sam Moody - Chief Executive

Stewart MacDonald - Chief Financial Officer

Tel. +44 (0) 20 7830 9704 (via Vigo Communications)

Canaccord Genuity Limited (NOMAD and Joint Broker)

Henry Fitzgerald-O'Connor

Tel. +44 (0) 20 7523 8000

Peel Hunt LLP (Joint Broker)

Richard Crichton

Tel. +44 (0) 20 7418 8900

Vigo Communications

Patrick d'Ancona/Ben Simons

Tel. +44 (0) 20 7830 9704

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 ("MAR").