Ukraine: Anger over Russian oil tanker due in Orkney
Russian ships could have their access to UK ports restricted, under plans being considered at Westminster.
It follows concerns that a Russian-owned tanker is due at an Orkney oil terminal within days.
Orkney Islands Council has said it is powerless to prevent the NS Champion accessing Flotta oil terminal, despite growing anger on the islands.
The tanker is owned by Sovcomflot (SCF Group), a large shipping company majority-owned by the Russian state.
It is due at Flotta to collect crude oil on Tuesday.
The prime minister has been urged to take action to deny Russian-owned vessels access to all UK ports.
A UK government spokesman said: "We are aware of concerns about Russian-connected ships potentially docking in the UK and we are working rapidly to explore a range of measures to restrict access for them.
"We are already discussing this issue with the Scottish government and the sanctions being considered are part of a wider package being worked up across the UK government."
Russia has been subject to a series of increasingly severe sanctions since invading Ukraine, including a ban on its planes in EU and UK airspace.
Sovcomflot is also currently subject to US sanctions limiting its ability to raise money through the US markets.
However Orkney Islands Council, which is responsible for the islands' ports and harbours, said it had been advised by the UK government that the tanker was not covered by current UK sanctions.
"As a council we are in an extremely difficult position," a spokesman said.
"We recognise the strength of feeling around this - feelings that we share - but we are bound by our legal obligations to accept the vessel, until such a time as the UK government tells us otherwise."
Angus Robertson, Scotland's cabinet secretary for external affairs, told BBC Scotland's Sunday Show: "The UK authorities have got a big decision to take, on whether we are going to allow Russian-owned or charted vessels to dock in UK ports.
"The Scottish government is in discussions with the UK authorities about this particular case but there will be others.
"This is a very fast moving situation and we're going to have to act decisively in my view."
At a protest against the Russian invasion of Ukraine in Orkney on Saturday, demonstrators spoke of their anger over the Russian tanker plans.
Nataliia Kuzmina, a Ukrainian living in Orkney, said her parents will not leave Ukraine. Her 56-year-old father has volunteered to join the fight to defend his town - but they don't have any weapons.
She said she was disgusted that the oil tanker was due to arrive in the islands.
"I feel that we have to do something about it," she added.
"This is a very real way for Orcadians to play their role in this whole situation and to show that they support Ukraine in this way.
"Every little thing matters now. Hundreds of people around Europe will do some small act like this, stopping buying Russian products, stopping tankers being filled up with oil.
"It matters and I feel it's my duty to turn away this tanker from Scapa Flow."
'Act without delay'
Orkney and Shetland MP Alistair Carmichael has written to Boris Johnson urging him to take action.
"Like right thinking people across the United Kingdom, the people of Orkney have been sickened by what we have seen on our television screens of the Russian attack on Ukraine," he wrote.
"We expect you, as our prime minister, to act to stop this continued trade that is earning money to fund the slaughter of Ukrainian citizens."
He added: "It is imperative... that you should act without delay to ensure that Sovcomflot is sanctioned and denied access for their vessels to British ports."
Scapa Flow played a key role during World War Two, and it is where 835 men and boys drowned when the Royal Oak was torpedoed by a German U-boat.
Mr Carmichael said: "To allow Sovcomflot to operate without let or hindrance in Scapa Flow would be to dishonour the memory of the sacrifice that the crew of the Royal Oak made in their fight against fascism of the sort that is currently engaged in attacking the people of Ukraine."
A spokeswoman for Repsol Sinopec, which operates the Flotta oil terminal said the NS Champion was due to arrive on Tuesday.
"We are liaising with regulatory authorities regarding the appropriate provision of access to facilities," she added.
Sovcomflot has been approached for a comment.
Russia attacks Ukraine: More coverage
- LIVE: Latest updates from on the ground
- THE BASICS: Why is Putin invading Ukraine?
- ZELENSKY: Comedian president rises to the moment
- DNIPRO: Terrified residents jolt into action
- PHOTOS: Ordinary lives turned upside down