UK independent EnQuest is planning to cut 80 jobs at its Sullom Voe Terminal (SVT) in the Shetland Islands.
About 60 permanent employees and 20 contractor roles are to go, about a quarter of the workforce.
EnQuest insisted the cuts were necessary for the terminal to remain competitive and to retain and win business.
The Unite union has been informed that EnQuest will open a six-week consultation on 23 July.
