Irish oil and gas company Petroceltic International has confirmed the sale of an 18.4 per cent stake in the Isarene natural gas field production sharing contract (PSC) to Sonatrach, the national oil and gas company of Algeria.

The transfer agreement was signed by Sonatrach, Petroceltic and Enel at a ceremony in Algiers on 12 February 2014. The deal has since been ratified by the Algerian Council of Ministers and was publicly announced on 7 July.

Sonatrach agreed to pay $20m on completion of the transaction as well as a further $140m to cover project development costs. Further payments of up to $20m are based on the achievement of project related milestones.

Upon completion of the transaction Sonatrach will hold a 43.4-percent participating interest in the Isarene PSC, while Petroceltic will hold 38.25 per cent and Enel will hold 18.4 per cent.