Exploration Drilling Update

PREMIER OIL PLC

("Premier")

Exploration drilling update

23 November 2011

As announced today by the Norwegian Petroleum Directorate, the Premier-operated exploration well, 9/1-1 S, known as Gardrofa, in PL406, offshore Norway has drilled to a total depth of 2,205 metres. The well is being plugged and abandoned as a dry hole.

Premier's Central North Sea exploration drilling focus will now turn to the UK. The Erne exploration well, which is targeting an Eocene Tay Formation, is presently drilling and the results are expected imminently. Upon completion of EnCore's Tudor Rose appraisal well, which spudded on 17 November, the Sedco 704 rig will drill the Premier-operated East Fyne appraisal well. The rig will then move to spud the Bluebell prospect in early 2012. In PL1430, the Catcher area licence, the 3D seismic acquisition programme has been completed and the next well on the licence (Carnaby) is due to spud in the first quarter of 2012.

In Vietnam, the Chim Sáo development well, S9-P, was deepened to a total depth of 4,333 metres subsea to assess the potential of the Oligocene sequence directly beneath the already producing Chim Sáo field. The well encountered 37 metres of gross Oligocene (Cau formation) sands with an estimated 17 metres of net hydrocarbon bearing pay. Elsewhere in Asia, the Anoa Deep well is expected to spud in early 2012 and the Biawak Besar well, also in Natuna Sea Block A, Indonesia, will be drilled immediately thereafter.

Simon Lockett, Chief Executive, commented:

"Whilst the Gardrofa well demonstrates our capability to drill operated wells in Norway, it was not an exploration success. However, the successful Chim Sáo test has added new resources and confirmed to us the importance of the Oligocene play in the Nam Con Son Basin. Exploration drilling will now focus on the Central North Sea Tertiary play fairways with six exploration wells over the next six months before returning to Asia in 2012."