Finland's navy chief says Russia's presence in the Baltic Sea may have peaked for now

Russia may have reached the limit of its "peacetime" ability to project force in the Baltic Sea, with the maritime situation "tense" but "stable", the head of Finland's navy has said.

Rear Admiral Tuomas Tiilikainen was speaking to Sky News as a team of US Marines briefly joined a NATO mission tasked with detecting and deterring hostile Russian activity in the area.

This includes attempts by sanctioned Russia-linked shadow fleet vessels to damage or spy on vital underwater data cables, power lines and other critical infrastructure.

"They [the Russian navy] monitor what we do, what NATO does, and we obviously need to monitor and maintain a vigilant guard on what they do and their activities," the Finnish naval chief said in an interview.

"But at the moment, I need to stress, even though the situation at sea is tense, it's still stable and there is no need for us to escalate the situation any further - rather de-escalate."

Rear Admiral Tiilikainen, speaking outside his naval base in Turku, a city on Finland's southwest coast, offered two possible reasons as to why the situation was stable.

"They [the Russians] see that there is no immediate need to ramp up their presence or their readiness in the region, but also maybe they have reached the limits of their capability in peacetime as they like to see here in the Baltic Sea," he said.

NATO allies established their Baltic Sentry maritime mission in January last year to enhance surveillance - from ships and from aircraft - of the Baltic Sea after a series of suspected acts of sabotage against undersea cables and power lines.

Elements of Russia's shadow fleet have been the prime suspects.

A Finnish court last week convicted the captain and another crew member of sabotage after their cargo ship damaged two undersea telecommunications cables linking Finland and Estonia in December 2025. The captain is reportedly a Russian national.

Rear Admiral Tiilikainen said there have been no further attacks against any Finnish undersea infrastructure since that incident.

Moscow is also suspected of spying on the undersea infrastructure of NATO allies across Europe, including around UK waters, identifying and mapping potential vulnerabilities that could be exploited in the event of war.

It is why the alliance has stepped up its own sea patrols.

A NATO military official said there are typically at least three NATO warships for every Russian military vessel in the Baltic Sea, with the ratio currently believed to be around 4:1.

Allies have also started to board certain shadow fleet vessels, with at least 13 interdictions believed to have taken place this year alone across Europe.

The willingness of NATO to take such action has forced Russia to increase its naval patrols in part to offer protection to the shadow fleet.

However, the NATO official said that this increased tempo was placing additional strain on Russia's already ageing warships as well as the crews.

"One of the big impacts [of Baltic Sentry] is a tax on their [Russia's] readiness if they are constantly away and on operations," the official said.

"In the past six months we have seen things [Russian naval patrolling] start to track down because of maintenance and readiness problems," they said.

"The numbers have gone down a tick."

The Finnish navy commander said he too believes NATO allies are having an effect with their patrols and by calling out Russian shadow fleet activities.

"Most probably the deterrence has worked today," he said.

"Maybe that trick has played its role now and there's no need to escalate because we have demonstrated that we are able to counter those threats."

Traffic from the shadow fleet of civilian tankers and cargo vessels has remained constant, however.

Rear Admiral Tiilikainen said the biggest risk in the Baltic Sea - which is framed by NATO states, including Finland, Sweden and the three Baltic nations - was an accident involving one of those vessels.

"At the moment, the biggest threat is the unprofessional crews of the shadow fleet and the tankers, the very old tankers," he said.

"They might create sort of a natural catastrophe if, let's say, a tanker runs aground."

A small group of US Marines has spent the past few weeks on a remote Finnish island, called Uto, conducting reconnaissance missions as part of the Baltic Sentry presence.

(c) Sky News 2026: Finland's navy chief says Russia's presence in the Baltic Sea may have peaked for now