Production on one of Ithaca Energy’s North Sea platforms has been shut down due to a Covid-19 outbreak on board.
The FPF-1 floating production facility has seen four people confirmed with the virus since Tuesday, who have now been taken off the rig.
Meanwhile, several other crew members who were in close contact are now in quarantine on board and awaiting transport to shore, under supervision of the on board medic.
Ithaca Energy said it will “not seek to restart production until we are confident that the virus has been eradicated from the platform”.
The firm said it is taking several measures, including moving to minimum manning levels on board.
Ithaca is also conducting a deep clean and implementing testing of “those essential personnel remaining onboard the platform”.
The quarantined crew will be downmanned “as soon as possible” the company said.
Public Health Scotland and the Health and Safety Executive have been notified.
An Ithaca Energy spokesman said: “The safety and wellbeing of our workforce is our top priority. Production on the FPF-1 has been shut in to ensure the safety of all those onboard.
“We are moving to minimum manning, conducting a thorough deep clean, and implementing testing of those essential personnel remaining onboard the platform.
“We will not seek to restart production until we are confident that the virus has been eradicated from the platform and we can start up in a safe and controlled manner.”
The FPF-1 lies around 150 miles east of Aberdeen.
Oil and gas is considered a “key” sector, meaning crews continue to work while the rest of the UK remains under tough lockdown restrictions.
The outbreak follows a similar situation on the Apache Forties Bravo platform this week, as well as cases on the Rowan Stavanger in Norway at the start of the month.
At the end of last year, the FPF-1 also made headlines after crew members became “submerged to their chest” in water inside an elevator shaft after a safety malfunction.
Ithaca said it was launching a full investigation.