Maintenance work on the Buzzard oilfield has been delayed until September – two months after it was expected to take place.
According to reports, the work had been planned to begin in July.
Buzzard produces about 180,000 barrels per day (bod) and is the largest contributor to the Forties crude oil stream, one of four grades of oil that underpin the dated Brent benchmark.
A spokeswoman for the operator, Nexen, declined to comment on the delays to the work.
But sources have said the work will begin in mid-September and run for around a month.
A spokesman said:“Nexen Petroleum UK Limited can confirm that a planned turnaround for Buzzard is scheduled for 2016.”