For Poland, the Baltic Sea region has become over the last few years an area of growing relevance. Once primarily viewed as a Central European country, Poland is now increasingly seen as part of the Baltic or Northern region.
The dispute over where the geographical centre of Europe lies has been ongoing for centuries. Central European countries such as the Czech Republic, Slovakia and Hungary – as well as Baltic Sea neighbours like Poland, Lithuania, Estonia and Sweden – have all laid claim to this symbolic status. While there are rational arguments behind each of these claims, viewing the region solely through the prism of geographic centrality is insufficient.
Historically, the Baltic Sea has held strategic significance, a status that has only intensified since Russia’s full-scale invasion of Ukraine. Since then, European political and elite circles have started to pay closer attention to the EU’s Eastern Neighbourhood, including the activities of the Russian Federation in the Baltic Sea. The Kremlin uses this region to assert influence and challenge the West, reflecting its imperial ambitions to surpass Europe militarily and economically.
As the war in Ukraine continues, Russia exploits the Baltic Sea to bypass sanctions and destabilize European states and their societies. The tensions it stirs are not limited to traditional military threats. They also involve unconventional tactics. An illustrative example is the so-called “shadow fleet”, a term used to describe vessels with unclear ownership operating in the Baltic without proper documentation. Russia employs them to circumvent western sanctions, especially those targeting oil exports.
Evidence shows that the Kremlin has deployed a wide range of instruments to exert influence in the Baltic Sea region. These include attacks on critical infrastructure, the disruption of data transmission, acts of cyber-terrorism, disinformation campaigns, and espionage. All of them serve the purpose of undermining the security and cohesion of societies in the region. Given their broader implications, these developments should be regarded as integral to the overall security situation of the European continent.
Equally important for European security – though in a positive light – is the cooperation among Poland, Lithuania, Latvia, Estonia, Denmark, Finland, Sweden and Norway in supporting Ukraine. They assist Kyiv both in its defensive efforts against Russian aggression and politically in its pursuit of integration with the European Union. According to estimates from the Kiel Institute for the World Economy, the Baltic Sea states are among the top aid donors to Ukraine. Estonia and Denmark each contribute 2.3 per cent of their GDP, followed by Lithuania (1.9 per cent), Latvia (1.5 per cent), Finland (1.1 per cent), Sweden (one per cent), and Poland (0.8 per cent).
Beyond military aid, Baltic Sea countries have taken proactive steps to strengthen regional security. In February 2024, Latvia initiated the creation of a drone coalition, now made up of 19 states. Although not all are located in the region, they share a commitment to investing in drone production for Ukraine and providing military training for civilians. The second funding stream aligns with the “whole-of-society” approach outlined in the EU Preparedness Union Strategy announced in March 2025.
Inspired by comprehensive resilience policies from the Nordic countries, this new EU strategy proposes a holistic approach to security It calls for the involvement of state institutions, the private sector, public organizations and NGOs in addressing security and resilience. Lithuania, Latvia and Estonia have already adopted this model. Other distinctive features of the Baltic states’ cooperation include the synchronization of their electricity grids and a focus on high-tech development.
For Poland, the Baltic Sea region has become over the last few years an area of growing relevance. Once primarily viewed as a Central European country, Poland is now increasingly seen as part of the Baltic or Northern region. This shift reflects its shared threat perception with countries such as Lithuania, Latvia, Estonia, Finland, Sweden, Norway, Germany, Denmark and the Netherlands. As a result, Poland’s bilateral and multilateral relations with these countries serve as the foundation for its new northern policy. Poland proposed strengthening Baltic Sea control and supported the NATO “Baltic Sentry” mission. Additionally, a new maritime strategy named “Polish Sea” was unveiled by the Prime Minister Donald Tusk in May 2025, aimed at boosting security and protecting critical undersea infrastructure.
Thus, when Szymon Hołownia, the Polish parliamentary speaker, announced the concept of the “Baltic Triangle”, he was referring to a close partnership among the Nordic countries, the Baltic states and Poland. While regional cooperation in the Baltic Sea area is built primarily on defence and resilience, this initiative would also encompass efforts toward the reconstruction of Ukraine. In this sense, it could also become a key element of the EU’s post-war strategy for Ukraine.
The accession of Finland and Sweden to NATO marked a significant development for the region, even though both countries had already been actively involved in NATO operations and broader regional cooperation. Recognizably, their formal membership, while undeniably enhancing the Alliance's military strength, carries an important psychological impact. It is particularly appreciated by the smaller states, such as Latvia or Estonia, which hope that any potential attack from Russia on their territory would trigger a quick response from NATO member states. It is also appreciated by Poland.
With NATO now expanded in the region, there has been a noticeable increase in air force monitoring, which takes place over the northern parts of the Baltic Sea, and in logistical support for the Baltic fleet, which tracks the movements of the Russian shadow fleet in the eastern basin. Additionally, Finland and Sweden are now working to secure access to the North Atlantic, a zone of both political and military importance, which is also very much welcomed by Poland.
The views and opinions in this text do not necessarily reflect those of the Heinrich-Böll-Stiftung.