North Sea firm Trapoil says remedial work to fix a shut-in well on the Athena field will not be carried out until later this year.
The Ithaca-operated well has been shut since August last year, after problems with the electric-submersible plumbing on the site.
Trapoil, which holds a 15% stake in the field, said Athena was currently producing at a reduced rate of 7,000 barrels a day. Work on fixing the problem is not expected to happen before the spring.
“We continue to evaluate the most appropriate course of remedial action with the operator and our other field partners with such work planned to be carried out later this year,” the company said.
“At this stage, the rate of depletion for Athena cannot be reliably predicted, but this is expected to become more evident as the water cut rises during the year.”
The firm said it had also been given an extension to the Surprise and Nutmeg North Sea discoveries, after picking up the Moray Firth finds from Dana Petroleum last year.
Trapoil said it was looking to farm out the finds, which are thought to contain around 12million barrels of oil.
The firm, which has formed a consortium with Taqa, Cieco and Japan Petroleum for the next round of UK offshore licences, said it retained cash reserves of around £16million.