Drilling Update - Anoa Deep

PREMIER OIL plc

("Premier" or "the Company")

Drilling Update - Anoa Deep

5th March 2012

Premier is pleased to announce that the Lama formation within the Anoa field on Natuna Sea Block A has been successfully tested.

As per the announcement on 6 February 2012, the WL-5 development well on Natuna Sea Block A was deepened to a total depth of 11,012 feet to investigate the exploration potential of the Lama Formation within the Anoa Field. The well encountered approximately 300 feet of fractured Lama Sandstones.

The Lama formation has now been tested over the interval 10,658 feet MD to 10,770 feet MD and flowed gas at a rate of 17 mmscfd through a 48/64 inch choke. The results of the test will be integrated with the log and seismic data to determine the ultimate recoverable resource of this deeper reservoir that will be produced through the Anoa facility.

The West Callisto rig will move to drill the Biawak Besar prospect on Natuna Sea Block A. The results of this well are expected in April 2012

Premier operates and holds a 28.667% interest in Natuna Sea Block A and is partnered by KUFPEC Indonesia (Natuna) BV, Hess and Petronas.

Simon Lockett, Chief Executive Officer, commented:

"We are very encouraged by this successful well test which has opened up deeper potential on this prolific gas block."

Enquiries

Premier Oil plc 020 7730 1111

Simon Lockett

Andrew Lodge

Pelham Bell Pottinger 020 7861 3232

Gavin Davis

Henry Lerwill