East Fyne appraisal well

PREMIER OIL plc

("Premier" or "the Company")

East Fyne appraisal well

4 April 2011

NOT FOR DISTRIBUTION TO U.S. NEWS WIRE SERVICES OR DISSEMINATION IN THE U.S.

Premier is pleased to announce that it has exercised its option, as announced on 7 October 2010, to drill the East Fyne appraisal well in the UK Central North Sea under the Joint Venture and Earn-In Agreement with Antrim Energy Inc. ("Antrim").

Under the terms of the agreement, Premier will have a 39.9 per cent operated interest in Block 21/28a containing the Fyne field in return for carry of up to US$50 million towards the development costs, including the East Fyne appraisal well. The licence assignment and transfer of operatorship under the Agreement is subject to partner approval and to the usual UK government approvals.

Antrim retains 35.1 per cent interest in the block and a 100 per cent working interest in the adjacent Blocks 21/28b, 21/29c, 21/24b and 21/29d (Greater Fyne Area). First Oil Expro Limited retains an interest of 25 per cent in Block 21/28a.

The agreement also provides Premier with the option to participate at a working interest of up to 50 per cent alongside Antrim in a planned drilling programme scheduled to start as early as the second quarter of 2011 in the Greater Fyne Area.

The East Fyne appraisal well is designed to de-risk the eastern extent of the Fyne Field in Block 21/28a and is expected to be drilled in the second half of 2011.

Simon Lockett, Chief Executive Officer, commented:

"Where Premier sees good opportunities, we will continue to invest in the North Sea. This agreement is an excellent example of our ability to utilise our strong financial and operating capabilities to build in our core areas."

Enquiries

Premier Oil plc 020 7730 1111

Simon Lockett

Pelham Bell Pottinger PR 020 7861 3232

Gavin Davis

Henry Lerwill