TALKS aimed at averting strike action at one of Europe's largest oil and gas terminals have broken down, union leaders say.

Unite accuses Shetland Islands Council of having made "no movement" to resolve the dispute which could trigger major disruption in Scotland's lucrative oil and gas sector.

An overtime ban is now set to begin, with potential strike action to follow.

The issue revolves around towage workers at the Sullom Voe terminal, which changed hands from BP to EnQuest in 2017.

Tug and towage staff working there transferred to Shetland Islands Council in 2006 and around 40 of these employees are now locked in an industrial dispute with the local authority.

Unite says they've suffered "unjust" treatment after being denied a service award as a result of that transfer. While other council workers recieve the equivalent of one month's salary after serving 25 years, the towage staff are to be paid the lesser sum of £250.

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A seven-week overtime ban will begin early next month and will "hugely disrupt" the multi-million pound contract to bring oil tankers on to the shore for oil processing, according to Unite, as well as production for the Brent and Ninian fields.

Industrial officer John Clark said: "Unite has continually been thwarted by the intransigence of the Shetland Islands Council over the long service award.

"The towage workers are asking for equal treatment which for 15 years has been denied to them since their transfer. This situation is completely unacceptable and unjust.

"Unless the council accepts liability, then industrial action will commence on the 5 July initially for seven weeks.

"We also have a mandate to take strike action which will be an inevitable course if the council doesn’t see sense. The overtime ban will hugely disrupt oil processing and production, having a serious impact on a multi-million pound contract."

Maggie Sandison, Shetland Islands Council chief executive, said: "We are disappointed to have received notification of Unite’s intention to take industrial action. 

"We remain committed to welcoming our towage staff into the council’s standard terms and conditions of employment and resolving this dispute. The towage staff are currently on a package of protected terms and conditions after transferring into the council and therefore we are unable to award one council benefit in isolation.

"It is our view that negotiations are ongoing and the next meeting is scheduled for this Friday 25 June."