A Resilient
Baltic

OSW Team · Baltic Sea Security

A Resilient
Baltic

Security of energy and port infrastructure and of maritime and air navigation

A body of water on which the energy supplies, foreign trade and military logistics of NATO’s eastern flank depend — and which is coming under growing pressure from Russian hybrid activity.

Read the key points ↓ osw.waw.pl

88%

of the gas consumed by Poland, imported via Baltic Pipe and Świnoujście (2025)

>40%

of the value of Poland’s foreign trade handled through Baltic ports

122k

flights reporting GNSS interference (Jan–Apr 2025)

~700

‘shadow fleet’ tankers on EU, UK and US sanctions lists

Report in Polish (PDF) Report in English (PDF)

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Key Points

Five areas of Baltic security under growing pressure

The OSW report analyses five pillars of the region’s security and shows where coastal states are catching up — and where capabilities and coordination are still lacking.

●I · Infrastructure

Physical damage to pipelines and cables between 2023 and 2025 exposed a gap in the capacity to protect and repair undersea energy and telecommunications infrastructure.

●II · Seaports

Espionage, unauthorised drone flights and daily cyberattacks are forcing Baltic ports to implement security measures in the absence of coherent EU-wide regulations.

●III · Maritime shipping routes

Chemical weapons and mines from both world wars, as well as Russian GPS/GNSS jamming, threaten navigation in one of the world’s busiest waters.

●IV · Shadow fleet

Uninsured tankers operating under false flags — the so-called ‘shadow fleet’ — handle the majority of Russia’s crude oil exports from the Baltic, systematically undermining maritime safety standards.

●V · Airspace

GNSS jamming in the Kaliningrad and St. Petersburg regions, as well as flights by Russian military aircraft without transponders, reduce the predictability of air traffic over the region.

“Ensuring the security of energy and telecommunications infrastructure, freedom of maritime and air navigation, and resilience to Russian hybrid activity is becoming one of the most important challenges for the states of the Baltic Sea region.”

Chapter I

Security of energy and telecommunications infrastructure

Baltic pipelines, power and telecommunications cables, and LNG and oil terminals are often of strategic importance to the coastal states. Linear infrastructure (cables and pipelines) has been regularly damaged over recent years, and attributing intent to those responsible in such cases is extremely difficult, particularly beyond the territorial sea.

80%+

of the gas consumed by Lithuania passes through the LNG terminal in Klaipėda (2025)

45%

of Poland’s imported gas is carried by Baltic Pipe (2025)

26%

of Finland’s energy consumption comes from coastal nuclear power plants (2024)

documented incidents of damage to cables and pipelines, 2022–2025

Selected offshore and coastal energy infrastructure in the Baltic Sea

Regional security relies on a dense network of LNG terminals, oil and fuel terminals, refineries, offshore platforms, nuclear power plants, and offshore wind farms along the entire Baltic coast. The map below compiles this infrastructure point by point — click a point to see details, or select a category from the filters.

Full-scale LNG terminals Small-scale LNG terminals Oil and fuel terminals Refineries ORLEN Petrobaltic drilling platforms Baltic Power offshore wind farm Nuclear power plants Active offshore wind farms

National measures

The states of the Baltic Sea region have taken measures to strengthen infrastructure protection. These have included operational involvement by law enforcement authorities, legal and regulatory changes to improve prevention and make responses to incidents more effective, and closer cooperation between military and civilian actors.

NATO measures

NATO has given greater attention to the security of critical undersea infrastructure since 2022.

EU measures

The European Union, complementing NATO’s activities, is developing framework-level solutions for protecting critical maritime infrastructure.

Recommendation

The states of the region should prioritise the full transposition of the CER and NIS2 Directives into their domestic legal orders, particularly regarding the protection of newly emerging maritime infrastructure, such as wind farms.

Recommendation

A realistic appraisal of the personnel and equipment available to maritime border guard and police units in the region clearly indicates the need for wider use of unmanned systems for monitoring, surveillance, and protection of maritime infrastructure, as well as for controlling shipping.

Recommendation

The key requirement, in addition to investment in prevention and crisis response, is to acquire the capabilities to rapidly repair maritime infrastructure.

Recommendation

There is a case for seeking areas for closer regional cooperation (including within the Council of the Baltic Sea States) because threats to maritime energy and telecommunications infrastructure are cross-border.

Chapter II

Security of Baltic Sea ports

Baltic Sea ports are of strategic importance to the economies of the region’s states, underpinning trade and supplies of key commodities, as well as — increasingly — energy security. They also play a key role in military logistics: they handle shipments of military equipment, including supplies to Ukraine, and play an important part in the movement of troops.

641m tonnes

record bulk cargo throughput at Baltic ports in 2025 (excluding Russia)

10m+ TEU

record container throughput at Baltic ports in 2025

90%+

of Poland’s container market is jointly handled by Gdańsk and Gdynia

100%

of the ORLEN Group’s refinery needs are supplied by Gdańsk’s Naftoport

In 2025, Baltic ports set new cargo throughput records while simultaneously facing daily cyberattacks, military and economic espionage and unauthorised drone flights over fuel terminals.

The largest ports on the Baltic Sea have long been Gdańsk, Klaipėda, Gdynia, Gothenburg, Aarhus, the Szczecin–Świnoujście port complex, and Rostock. Gdańsk is the undisputed leader in container throughput in the Baltic Sea region — the Baltic Hub terminal, together with Gdynia, handles over 90% of Poland’s container market.

Gdańsk (Naftoport), Świnoujście (LNG terminal), and Gdynia (liquid fuel handling berth) are pillars of Poland’s energy security. Naftoport meets all of the requirements of the ORLEN Group’s Polish refineries and supplies crude oil to the refinery in Schwedt, Germany.

At present, seaports must increasingly focus on implementing security measures, yet they lack adequate EU rules to draw on. For the most part, such solutions are introduced either by ports on their own initiative or by individual EU member states.

Recommendation

Further strengthening cooperation among EU member states and port authorities within the framework of the EU and the Council of the Baltic Sea States, including the exchange of experience and information on security-related incidents.

Recommendation

Increased EU funding for dual-use infrastructure — the current criteria (e.g. the requirement for a minimum quay depth of 14 metres) exclude some ports.

Chapter III

Security of maritime shipping routes

The Baltic is among the busiest seas in the world — shallow, with traffic concentrated in the narrow Danish Straits and with hazardous remnants of two world wars on the seabed.

8–10k

shipwrecks and vessels on the Baltic Sea floor (HELCOM estimate)

40k tonnes

tonnes of chemical munitions dumped at sea after the world wars

52 m

the Baltic Sea’s average depth — limits navigation conditions

2k+

large merchant vessels at sea at any one time

The risk to shipping comes from two main sources. The first is the physical legacy of wars — approximately 40,000 tonnes of chemical munitions and over 200,000 tonnes of conventional munitions and explosives dumped in the Bornholm Deep and the Gotland Deep during and after the First and Second World Wars, whose continued degradation may lead to environmental disasters and may also be used to conceal sabotage. The second is the systematic jamming and spoofing of GPS/GNSS signals mainly from the Kaliningrad Oblast and the St Petersburg area, forcing ports to implement alternative ship guidance systems.

Collaboration within HELCOM, NATO, and the European Union facilitates coordinated threat mapping, but a significant portion of the Baltic seabed has yet to be surveyed using modern sonar and magnetometric methods, and a regional programme for the systematic removal of the most dangerous wartime remnants does not exist.

Recommendation

A programme for the gradual neutralisation of the most dangerous remnants of war, alongside further intensification of seabed mapping.

Recommendation

Deepening cooperation between maritime administrations, ports, rescue services, and navies — primarily through regular joint exercises covering infrastructure failures and navigation disruptions.

Recommendation

The Council of the Baltic Sea States, as a platform integrating environmental protection, maritime security and critical infrastructure protection, should have a shared database and incident response procedures.

Recommendation

Extending the ‘Polish PNT Shield’ to other countries in the region in order to increase resistance to the jamming and spoofing of satellite navigation.

Chapter IV

Activity of Russia’s ‘shadow fleet’ in the Baltic Sea

Tankers operating in a legal grey area — without P&I insurance, under false flags and with manipulated AIS signals — carry nearly half of Russia’s seaborne oil exports, helping circumvent Western sanctions.

~⅓

of the total cargo throughput is handled by Russia’s Baltic ports

~700

‘shadow fleet’ tankers subject to EU, UK and US sanctions

~50%

of Russia’s seaborne exports of crude oil and petroleum products passes through Baltic Sea ports

documented incidents in the Baltic Sea involving ‘shadow fleet’ tankers (Jan 2023–May 2026)

Russian Baltic Sea oil terminals handle nearly half of the country’s seaborne exports of crude oil and petroleum products. Under Western sanctions, much of this trade is carried out by ‘shadow fleet’ tankers — vessels with an unclear legal status that manipulate AIS signals, conduct ship-to-ship transfers at sea and often rely on inexperienced crews reluctant to cooperate with navigators from EU member states. The environmental and escalation risks are particularly high in the Baltic Sea, which is semi-enclosed, has limited water exchange, and experiences high levels of maritime traffic.

Incidents and detentions of vessels, 2023–2026

The map below compiles the most important incidents in the Baltic Sea involving damage to critical infrastructure, environmental threats, and (attempted) detentions of ‘shadow fleet’ vessels. Click a point to see details — or select an event from the calendar alongside.

Critical infrastructure Environmental threats Vessel detentions

Recommendation

Maintaining and strengthening measures to restrict the shadow fleet’s shipping — inaction increases the risk of further deterioration in shipping conditions and environmental damage.

Recommendation

Exerting pressure — including through EU diplomacy — on flag states and jurisdictions in which the companies chartering shadow fleet tankers are registered.

Recommendation

Coordinating sanctions within the G7 — thanks to the threat of secondary sanctions, US restrictions are significantly more effective than EU ones.

Recommendation

Initiating talks on a maritime convention for the Baltic Sea that would allow the detention of vessels in exclusive economic zones if they fail to meet environmental standards.

Chapter V

Air traffic in the airspace over the Baltic Sea

Russian GNSS jamming and Russian military aircraft flying without their transponders switched on and without filed flight plans pose a significant risk to air traffic in the region. This leads to a local and temporary reduction in the predictability of the air traffic system.

1000–1200

average daily number of flights over the Baltic Sea (2025)

122k

flights reporting GNSS interference, January–April 2025

30+

documented airspace violations in the region since 2022

The airspace over the Baltic Sea is an important regional transport artery, and its role in passenger flights beyond Europe has grown since 2022. The average daily number of flights over the Baltic Sea in 2025 hovered between 1,000 and 1,200. Civil aviation made up the bulk of it, and as much as 40 per cent of those flights were regional — that is, they began and ended in a state of the Baltic Sea basin.

Air traffic control over the Baltic Sea is based on a multi-level airspace management system that combines the activities of national air traffic control services, international organisations and military structures.

Recommendation

Investments in alternative, multi-layer navigation systems combining satellite, inertial and ground-based technologies — following the example of the ‘Polish PNT Shield’.

Recommendation

Expanding capabilities to detect and neutralise unmanned aerial vehicles and further strengthening the NATO air defence system.

OSW Report 9/2026

Full analysis, tables and recommendations in the original report

Authors: Piotr Szymański, Jacek Tarociński, Filip Rudnik, Sandra Baniak-Stachowiak. Substantive editing: Justyna Gotkowska.

Raport po polsku Report in English