London-based oil and gas explorer Premier Oil has reached a deal to sell its stake of 33.8% in the Wytch Farm onshore oil field in the UK to Perenco UK for $200m in an all-cash deal.

The transaction sees Perenco UK exercising its pre-emption right as an existing partner in the field.

Prior to the deal, the Anglo-French oil and gas company Perenco held a stake of 53.8%. Ithaca Energy with a stake of 7.4% and Repsol Sinopec with a stake of 5% are the other participants in the Wytch Farm oil field which is spread across licenses PL089 and P534.

As a result of the new transaction, a deal made in September between Premier and Scotland-based Verus Petroleum stands cancelled.

The same terms that Premier had agreed to with Verus Petroleum will be applied in the transaction with Perenco, which has been the operator of the Wytch Farm field since 2011.

As part of the deal, Premier will be released from letters of credit that total up to $75m.

Premier previously stated that its exit from the oil field aligns with its track record of value realization of assets at the appropriate stage of their life-cycles through active portfolio management.

Its board had also concluded that the disposal of the Wytch Farm stake is in the best long-term interest of the company and its shareholders.

Premier forayed into the Wytch Farm field in 1984 by acquiring a stake of 12.4%. In late 2011, it raised its stake in the conventional oilfield to 30.1%.

Premier’s exit from the field comes only months after it had acquired an additional stake of 3.7% from Maersk Oil North Sea UK in July.

The Wytch Farm field is located in a highly environmentally sensitive area in the Dorset County and has been in production for nearly 28 years. It is considered to be the largest onshore oilfield in Europe.