Finland's national power grid operator said on Thursday it had asked a Helsinki court to seize the Eagle S oil tanker in a bid to secure the company's claim for damages related to the breakdown of the undersea Estlink 2 electricity interconnector.
The cable between Finland and Estonia was damaged on Dec. 25 along with four telecoms lines, and Finnish authorities the next day boarded the tanker, which carries Russian oil, on suspicion that it caused the damage by dragging its anchor along the seabed.
Baltic Sea nations are on high alert after a string of outages of power cables, telecom links and gas pipelines since Russia invaded Ukraine in 2022. NATO said last week it would boost its presence in the region.
Fingrid said in a statement on Thursday it had asked the Helsinki District Court to formally seize the Eagle S to help secure its financial claim.
"Further investigations at the damage site are expected to provide more information about the extent of the damages and enable more detailed planning and scheduling of the repair," Fingrid said.
The company said last week it expected the cable to come back into service in August this year.
A lawyer representing United Arab Emirates-based Caravella LLC FZ, which owns the ship, did not immediately respond to a request for comment. The owner has previously asked that Finnish authorities release the vessel.
Finland's customs service has said it believes the Eagle S is part of a shadow fleet of tankers used to circumvent sanctions on Russian oil, and has formally impounded its cargo although the cargo is still on board the ship.
Moscow has said Finland's seizure of the ship is not a matter for Russia.