On Christmas Day, the Estlink 2 electricity cable and four telecom cables linking Finland and Estonia were damaged, just weeks after other Baltic Sea cables were severed in similar incidents that experts and politicians say are part of a hybrid war between Russia and Western countries.

The January 14 meeting in Helsinki will focus on "measures required to secure the critical underwater infrastructure", a statement from the office of Finland's President Alexander Stubb said.

"The discussion will focus on strengthening of NATO's presence in the Baltic Sea and responding to the threat posed by Russia's shadow fleet."

The "shadow fleet" consists of ships that carry Russian crude oil and petroleum products embargoed over Moscow's invasion of Ukraine.

The often ageing vessels operate under dubious ownership or without proper insurance.

Among those due to attend the meeting are NATO Secretary General Mark Rutte, the leaders of Denmark, Germany, Latvia, Lithuania, Poland and Sweden, and the executive vice-president of the European Commission Henna Virkkunen.

Finland's President Alexander Stubb and Estonian Prime Minister Kristen Michal will co-host the meeting.

Suspicion over the December 25 incident has fallen on the Eagle S, a Cook Island-flagged oil tanker thought to be part of the "shadow fleet".

Finnish police seized the vessel on December 28 as part of a criminal investigation into suspected sabotage.

The ship is anchored in Porvoo, a town east of Helsinki. Finnish authorities have banned eight crew members from leaving the country during the police probe.

Investigators suspect the cables were damaged after the tanker's anchor was dragged over them.

On Tuesday, police said the Eagle S anchor had been recovered from the seabed.

NATO announced late last month that it would strengthen its military presence in the Baltic Sea in responses to the cable cuts.

Finland became a NATO member in 2023, dropping decades of military non-alignment after Russia's invasion of Ukraine in February 2022.