BP has shut down production at an oil platform west of Sheltand after oil was released into the water.
The Clair platform was shut down on Sunday for what BP blamed on a “technical issue”.
No details have been releases on the size of the leak or how long the company expects the platform to remain offline, though BP said the leak has been stopped.
The UK Government’s Department for Business, Energy and Industrial Strategy has been informed of the leak along with the Oil Spill Response Limited, the international industry-funded cooperative which responds to oil spills.
A BP spokesman said: “The Clair platform, which is located 75km west of Shetland, has been shut down and the release has been stopped.
“All personnel have been accounted for and there are no injuries.
“We are investigating the cause of the technical issue and monitoring the situation.
“All relevant authorities have been informed.”