(Sharecast News) - Oil field services company Petrofac on Friday said it was selling its interest in the North Sea's Greater Stella area to Ithaca Energy up to $292m.Proceeds from the sale of Petrofac's 20% interest in the Greater Stella Area development and its 24.8% interest in the FPF1 floating production facility would be used to cut debt. It will also result in a $55m impairment charge, the company said.Ithaca will pay $145m by or on completion and a further $120m of non-contingent deferred consideration in the period 2020-2023. A further $28m is payable depending on field performance.The transaction is expected to complete in the first quarter of 2019 and is subject to several conditions precedent, including completion of Ithaca's acquisition of Dyas UK's 25% interest in the Greater Stella Area development and its shares in the FPF1 company."This disposal marks a further milestone in our journey back to a capital-light business and, along with recently-agreed transactions in Mexico and Tunisia, marks the significant progress we are making on our stated strategy," said chief executive, Ayman Asfari.