Drilling Update

PREMIER OIL plc

("Premier" or "the Company")

Drilling Update - Burgman Side-Track Result

Premier notes that EnCore Oil, as operator of North Sea block 28/9, has today issued the following press release:

"EnCore Oil plc (LSE: EO.) is pleased to announce that the Burgman side-track well 28/9-4z located on UKCS Central North Sea Block 28/9 has successfully encountered hydrocarbons in the targeted Lower Tay sandstone interval.

The well was drilled directionally with a hole angle up to 64 degrees to a Total Depth of 5,237 feet Measured Depth (M.D.). Initial analysis indicates net oil pay of 135 feet over a gross reservoir interval of 135 feet (M.D.), equivalent to 64 feet of net vertical oil pay over gross vertical interval of 64 feet True Vertical Thickness. Preliminary log analysis indicates an average porosity of 38%, significantly better than in the original Burgman well. Initial estimates suggest a likely STOOIP in the range of 80 - 120 mmbbls.

This result now concludes the current drilling programme on Block 28/9 and following completion of this well, the Transocean Galaxy II heavy duty jack-up rig will be demobilised. The Galaxy II has drilled three successful wells during this drilling campaign, resulting in two substantial discoveries at Varadero and Burgman, and an appraisal of Catcher North."

Premier holds a 35% interest in the block.

Simon Lockett, Chief Executive Officer, commented:

"We are very pleased with the results of this sidetrack, which confirms the relationship between good quality reservoir and stronger seismic amplitude supported indicators. We look forward to the inclusion of Burgman in the development planning process as we take the Catcher area forward."

Enquiries

Premier Oil plc 020 7730 1111

Tony Durrant

Pelham Bell Pottinger PR 020 7861 3232

Gavin Davis

Henry Lerwill