Twelve Western countries agree to "disrupt and deter" Russia's shadow fleet

The measures were agreed by Germany, Britain, Poland, the Netherlands, the five Nordic nations and the three Baltic states, said Estonia, where leaders of the 10-nation Joint Expeditionary Force were due to meet on Tuesday.

Western nations have slapped sanctions on a wide range of ships they say are used by Moscow to avoid restrictions on the export of Russian oil and other cargoes. Vessels in the shadow fleet are not regulated or insured by conventional Western providers.

"We are taking concerted steps to deter Russia's shadow fleet and avoid attempts to evade sanctions," Estonian Prime Minister Kristen Michal said in a statement.

Denmark, Sweden, Poland, Finland and Estonia will begin to check insurance documents of ships under suspicion passing through the English Channel, Danish straits, the Gulf of Finland and the sound between Sweden and Denmark, he added.

Russia is disrupting mobile communications and ship-tracking data across the Baltic Sea, endangering vessels and energy supplies to test how Western powers will respond, a Polish admiral overseeing the area said.

Vice Admiral Krzysztof Jaworski said Moscow was systematically using such tactics to hide the movements of its own vessels and disrupt the operations of others in the sea which is bordered by eight NATO countries and Russia.

"Hybrid war in the Baltic is the biggest challenge we are facing," Jaworski told Reuters in an interview last week, referring to the practise of launching conventional attacks alongside attempts to disrupt politics, energy supplies and other systems.

"We are talking about aggressive behaviour by Russia. They are trying to disrupt our lives," added Jaworski, Poland's Maritime Component Commander. "They are also testing us, us as an alliance (to see) how far they can go."

Russia's defence ministry could not be reached for comment. Russia denies accusations that it is sabotaging countries in the West and accuses the West of seeking to sow discord inside Russia.

There have been at least three incidents of possible sabotage to the several dozen telecommunication cables and critical gas pipelines that run along the relatively shallow seabed since 2022, when Russia invaded Ukraine.

The head of Germany's foreign intelligence service, Bruno Kahl, said last month Russia's acts of sabotage against Western targets may eventually prompt NATO to consider invoking the alliance's Article 5 mutual defence clause.

On Monday the European Union adopted a 15th package of sanctions against Russia over its invasion of Ukraine.

The new package added 52 vessels from Moscow's so-called shadow fleet that tries to circumvent Western restrictions to move oil, arms and grain, bringing the total listed to 79.

Jaworski said Russian commercial vessels had switched off their Automatic Identification System (AIS) signals - which allow electronic navigation - dozens of times since the sabotage of the Nord Stream pipeline in 2022.

That broke maritime law, allowed vessels to move undetected and endangered other ships in the area, he said.

There were also efforts to block other ships' identification and tracking systems and disrupt them with false readings, he added. "We are dealing with jamming of mobile and positioning data and with incidents of false echoes."

Finland's Coast Guard made similar complaints in October, saying jamming has led to ships getting lost and losing their course.

Jaworski said it was impossible to keep a constant watch on all of Poland's waters in the Baltic, though he believed his country was safe thanks to its own and allies' operations.

He said NATO would keep its advantage in the region even if Russia moves more ships to the area, adding that the alliance could move its frigates usually positioned in the Atlantic and Mediterranean to the region to keep the balance.

Last week Poland's security bureau chief Jacek Siewiera said he expects Russia to relocate its naval vessels, including missile frigates currently in Syria to St. Petersburg - a journey that would take them into the Baltic Sea.

"Of course, every single additional ship of great strength can be a potential threat," Jaworski said.

Asked how Poland and its allies would respond to any such movement, he said they would limit themselves to observing, monitoring and being present at the sea "so that a potential adversary can also see that we are ready to act".

Poland receives most of its natural gas it uses via the Baltic in the form of liquefied natural gas (LNG) and pipeline shipments from Norway.