Russian-linked vessels surveying Baltic infrastructure: Polish study

Russian-linked vessels are increasingly surveying critical infrastructure in the Baltic Sea region, according to a new report by Poland’s state-funded Center for Eastern Studies (OSW).

The report, Resilient Baltic, warned that protecting energy and telecommunications infrastructure and maritime and air navigation has become a major security challenge for Baltic Sea states.

It also highlighted the need to strengthen resilience against what it described as Russian hybrid operations.

Russia has rejected claims accusing Western governments of stoking "anti-Russian paranoia."

The OSW study said vessels linked to Russia have been used to map seabed infrastructure and gather information on ports, terminals and quays.

It warned that apparently civilian maritime activity could also serve intelligence purposes.

The center said six cases of damage to undersea cables and pipelines were documented between 2022 and 2025.

It said establishing responsibility for such incidents is particularly difficult outside territorial waters.

The report said Poland is particularly exposed because more than 40% of the value of its foreign trade passes through Baltic ports.

It said the ports of Gdansk and Gdynia handle more than 90% of Poland's container market.

The center said Baltic ports also play a growing military role, including handling equipment destined for Ukraine and facilitating the movement of allied forces along NATO's eastern flank.

The report called for closer cooperation between Baltic governments and port authorities, greater information-sharing on security incidents and increased EU funding for dual-use port infrastructure.

It also highlighted growing activity by Russia's so-called shadow fleet -- tankers used to transport Russian oil while circumventing Western sanctions.

The center said around 700 tankers are currently subject to sanctions imposed by the EU, UK, or US.

It said approximately half of Russia's seaborne oil and petroleum-product exports pass through Baltic ports.

According to the study, around 122,000 flights reported satellite-navigation interference over the Baltic between January and April 2025.