Editor's note: This analysis was first published in Polish on 29 April 2026 as Trójmorze: dekada na rozliczenie, on the eve of the Three Seas summit in Dubrovnik (28 and 29 April 2026), and is written as a preview of that summit. The summit adopted the Dubrovnik Declaration, 'The Three Seas in Its Second Decade: Powering Europe's Strategic North-South Axis'. This English translation follows the Polish text as corrected on 21 October 2026.
Dubrovnik 2026: time to take stock
The Three Seas Initiative (3SI) is completing its first decade. The summit scheduled for 28-29 April 2026 will take place in Dubrovnik, the same city where the Initiative's founding declaration was signed in August 2016. The anniversary comes at the most difficult moment in the Initiative's history, shaped by three simultaneous developments: in Hungary, Péter Magyar's Tisza party has just won the elections (12 April 2026); Washington is shifting its strategic centre of gravity to the conflict with Iran; and Donald Trump's second term is redefining transatlantic relations. In these circumstances the Dubrovnik summit cannot be confined to anniversary matters.
The balance sheet of the first decade is mixed.
On the credit side, the region has largely freed itself from dependence on Russian energy, brought key external partners into the cooperation (Germany, the United States, Japan, the European Commission and, since 2025, Turkey and Spain) and built the Three Seas Initiative Investment Fund (3SIIF), with around EUR 1.1bn in committed capital and a target return of 12 to 15% a year. The region's economy is growing twice as fast as the EU average.
On the debit side, however, there is a vast investment gap, which will reach between EUR 650bn and EUR 1tn by 2030. The Initiative still has no permanent secretariat, no legal personality and no institutional tools to enforce its own decisions. Its funding structure is also strikingly lopsided: 80% of the 3SIIF's capital comes from a single country.
What is at stake in Dubrovnik, then, is the choice of a model for the future. Either the Three Seas turns into a fully fledged international institution, able to attract global capital and deliver transnational projects, or it stays as it is: an annual meeting of heads of state with side events attached.
The energy pillar: the effect of an external shock
Energy is so far the only area in which the Initiative has achieved measurable results. Russia's share of EU gas imports has fallen sharply, from 40% in 2021 to 12-13% in 2025. Gazprom cut off gas supplies to Poland in April 2022, and the Yamal contract expired at the end of that year; Russian pipeline oil stopped flowing to Poland in February 2023. The Baltic states synchronised their grids with the continental European network, disconnecting from the Russian power system in February 2025.
In autumn 2025 the gas transmission operators of Greece, Bulgaria, Romania, Moldova and Ukraine jointly asked their regulators to approve cheaper capacity products on the Vertical Gas Corridor, which carries LNG from Greek terminals through Bulgaria, Romania and Moldova to Ukraine. The process will be completed by the EU ban on Russian gas: from 1 January 2027 it also covers long-term LNG contracts, and pipeline gas follows in autumn 2027.
Member states are to phase out Russian oil imports by the end of 2027.
It should be stressed, though, that this transformation is not solely the product of the Three Seas format. Without Russia's aggression against Ukraine and the hard decisions it forced on EU member states, the process would have taken decades. The new arrangement also creates structural challenges of its own. US liquefied natural gas has become the main substitute for Russian supplies, now covering 60-70% of the whole region's imports. Western European countries (Germany, France), meanwhile, have retained partial access to Russian LNG shipped by sea. In effect, Central Europe has borne the real cost of independence, while Western European markets have kept partial continuity of supply.
The transport pillar: a delivery deficit
In infrastructure and transport, the Initiative's record is far weaker. Rail capacity on the strategic north-south axis remains wholly inadequate to the size and needs of the region's economies. A passenger journey by rail from Warsaw to Zagreb takes between about 17 and 20 hours and requires changes, and there is no direct passenger service at all between Gdańsk and Thessaloniki.
In Western Europe, by contrast, routes of similar length run along continuous TEN-T corridors such as the Scandinavian-Mediterranean corridor. The prospects for the flagship road project, the Via Carpatia linking Lithuania with Greece, are equally remote. The Polish section will be completed in 2026-2027 and the Slovak section by 2030, with the Romanian and Bulgarian sections in 2030 at the earliest.
Realistic estimates suggest that the route as a whole will not be fully operational until the 2040s.
The lack of capacity to deliver is best illustrated by Rail Baltica. The original cost estimate was EUR 5.8bn; current estimates put it at EUR 23.8bn, leaving a funding gap of some EUR 19bn. The budgets of the Baltic states cannot absorb a fourfold increase in costs. Although the project has not been formally cancelled, it no longer has any binding timetable.
There are three main reasons for this. First, cross-border projects require a strong coordinating institution, which the Three Seas does not have. The European Union manages such processes through mechanisms such as the Connecting Europe Facility (CEF) or the EU Strategy for the Danube Region; the 3SI has created nothing comparable. Second, national priorities clearly diverge.
Poland sees the Via Carpatia as a logistical and military artery towards Ukraine; Greece prioritises the IMEC corridor and links with Asian markets; Bulgaria looks mainly to the Black Sea basin, and Croatia to the Adriatic. Third, in the absence of an arbitrating institution, each country invests at its own national pace, without regard to regional logic.
A tangible measure of this lack of integration is the state of bridge infrastructure. Along the 458 km Romanian-Bulgarian border on the Danube there are just two bridges. By contrast, the 187 km stretch of the Polish-German border on the Oder has as many as 29 crossings. This is not merely a matter of geography; it is the direct result of investment policy in Central Europe over the past half-century.
The financial paradox: a lack of instruments, not of returns
The Three Seas Fund (3SIIF) targets an annual return of 12 to 15%, and according to the Atlantic Council it has delivered returns in that range. For pension funds and sovereign wealth funds active in infrastructure, that is a highly attractive figure. Even so, large institutional capital consistently bypasses the 3SIIF. Norway's Norges Bank prefers to invest in offshore wind in Germany and Denmark. Abu Dhabi's Mubadala is acquiring logistics assets in Europe through bilateral deals, and Singapore's GIC operates in Central Europe through purely corporate channels. Capital is flowing into Central Europe, but outside the official framework of the Three Seas Initiative.
Five years after it became operational in 2020, the fund's own record is mixed. Nine of the thirteen participating states have contributed capital totalling around USD 1bn, to which the US International Development Finance Corporation (DFC) added USD 300m. The fund has already committed more than EUR 800m in nine countries. The original goal of attracting USD 3-5bn in private capital, however, has not been met.
As Ian Brzezinski of the Atlantic Council noted in his latest analysis of 23 April 2026, the fund has almost exhausted its available capital. Dubrovnik therefore becomes the moment that forces a hard decision: either a thorough restructuring of the current 3SIIF or the launch of an entirely new mechanism.
There are two reasons for this. The first is operational scale. A fund of around EUR 1.1bn is too small to justify the costs of risk analysis and monitoring for managers of portfolios worth USD 100bn or so. For the largest market players, the threshold at which entry pays off starts at EUR 10-15bn. The Three Seas is, in other words, an order of magnitude short.
The second, and decisive, reason is the lack of an institutional framework. Large investors need partners with established legal personality, a prospectus, a credit rating, external audit procedures and transparent governance. The Nordic Investment Bank (NIB), which brings together the Nordic and Baltic states and is the natural benchmark, meets these criteria.
The Three Seas, by contrast, has only an annual summit, a rotating presidency and a network of national coordinators. It cannot issue bonds and has no permanent representation. The core problem, then, is not a lack of demand for investment but the absence of an institution able to translate political declarations into terms that global markets can price.
The conclusion is clear: without a Three Seas Development Bank and a permanent secretariat, private capital will not flow into the region on a scale that could close the investment gap. High returns cannot make up for the lack of a credible financial architecture.
The Polish dimension: cohabitation and the burden of funding
Poland's role in the Three Seas ecosystem is asymmetric in two ways. On the one hand, Warsaw remains the format's main initiator, its political face and its main funder. On the other, since August 2025 Poland's executive has operated under a fractious cohabitation, in which the presidency and the government pursue different visions of foreign policy.
President Karol Nawrocki, sworn in on 6 August 2025 after winning the election with the backing of the Law and Justice (PiS) opposition, has smoothly taken over this line from Andrzej Duda, keeping the Three Seas among the Presidential Palace's flagship projects. As early as January 2026, in Davos, he described the region as an 'engine of resilience' for Europe, and his visit to Washington in September 2025 secured a direct channel of communication with Donald Trump's new administration.
For the presidency, the 3SI is a geopolitical bloc of sovereign states in relations with the United States: complementary to the EU rather than in competition with it, and a means of strengthening Warsaw's international position. At present this is the only strategically coherent strand of Polish policy towards the format.
Donald Tusk's government (a coalition led by his Civic Coalition), by contrast, has yet to set out a clearly positive vision for the Initiative. In his policy address of April 2024, Foreign Minister Radosław Sikorski laid down a firm condition: 'The 3SI will be a success ONLY if it facilitates the development of the region's transport, energy and digital infrastructure from Estonia to Greece' (translated from Polish).
Rhetoric of this kind reduces the 3SI almost entirely to a logistical tool and sidelines its geopolitical ambitions. Yet the government has not offered a comprehensive alternative to the presidential vision. On 26 February 2026, in his annual foreign-policy address to the Sejm (the lower house of parliament), the foreign minister sent an unambiguous signal to the United States: 'We have been and will remain a loyal ally of America, but we will not be suckers' (translated from Polish).
The statement attracted media attention but did not lead to any concrete proposal for cooperation, either for Washington or for the capitals of the region.
The political cost of this dual messaging became visible at the 3SI summit in Warsaw in April 2025. Eleven heads of state attended, along with delegations from strategic partners (including the newly admitted Spain and Turkey). The host was President Duda. Prime Minister Tusk did not take part in the summit; on 28 April he held only a bilateral meeting with Croatian Prime Minister Andrej Plenković. For the capitals of the region the political signal was clear: the Initiative's main funder leaves its representation to one centre of power, while the other conspicuously keeps its distance from the Initiative.
The pattern was confirmed eleven months later. The Three Seas Parliamentary Summit in Zagreb (24 and 25 March 2026), held under the slogan 'Advancing the Three Seas Initiative: Vision, Responsibility, Partnership', brought together, among others, Croatian Prime Minister Andrej Plenković, speakers of parliaments from the region and EU Commissioner Dubravka Šuica.
Poland was represented by a Deputy Speaker of the Sejm, Szymon Hołownia, rather than by the Speaker. As this was a parliamentary summit, the absence of ministers is not in itself a failing. What is telling is that the government used none of the Initiative's meetings in this period to put forward a proposal of its own. Ian Brzezinski makes a similar point about the government's limited engagement in the Atlantic Council analysis cited above.
The government's approach was stated plainly by Deputy Foreign Minister Władysław Bartoszewski in October 2024, who said that 'the Three Seas Initiative (…) has gained additional importance precisely because of the changes that have taken place in other formats' (translated from Polish). In the government's view, therefore, the 3SI is not an autonomous strategic goal but rather a stand-in for the dysfunctional Visegrád Group.
Poland is thus sending two contradictory messages: strategic and proactive from the presidency, cautious and detached from the government. As a result, regional partners, among them Croatia (which holds the presidency), Romania and the Baltic states, are adjusting their operational plans on the assumption that Warsaw's incoherence in decision-making will persist for at least the next two years.
Hungary after Orbán: the end of an internal blockage
The parliamentary elections of 12 April 2026 ended sixteen years of rule by Viktor Orbán. Tisza won 141 seats in the 199-member National Assembly, reducing Fidesz to 52. The new government is expected to be formed in mid-May.
For the Three Seas, this removes a significant obstacle to decision-making. At the 2025 Warsaw summit, the outgoing Hungarian government still entered an opt-out from the passages of the final declaration condemning Russian aggression and calling for peace on Kyiv's terms. The winning party has already announced that it will drop this veto, unblock EUR 90bn in EU aid for Ukraine, phase out Russian hydrocarbons by 2035 and join the euro area by 2030.
The incoming foreign minister, Anita Orbán (no relation to Viktor Orbán), summed up the new course: Hungary must 'stop being a stick in the spokes and start being a spoke in the wheel'. Ukrainian diplomats have already confirmed that a direct working channel has been set up between Zelensky and Magyar.
The structural effects of this geopolitical shift on the 3SI format itself are nonetheless limited. The new government in Budapest removes the problem of political paralysis, but it cannot create the missing banking instruments or a permanent secretariat overnight. The Initiative sheds a reputational burden, but its institutional shortcomings remain unresolved.
A new hand in Washington: opportunities and risks
For Central Europe, US policy during Donald Trump's second term brings both opportunities and risks.
On the positive side, the DFC's investment cap has been raised (under the 2025 modernisation act) from USD 60bn to USD 205bn. Lending procedures within the US administration have also been integrated, and the United States-Ukraine Reconstruction Investment Fund has been set up (under an agreement of 30 April 2025), which receives half of the royalties and licence fees from natural-resource projects in Ukraine. American capital is also engaging in the region's nuclear sector (small modular reactors in Romania, AP-1000 reactors in Poland and Bulgaria, and advanced talks with Slovenia and Croatia).
On the other hand, systemic risks are growing. Washington's assertive tariff policy is hitting the export potential of its European allies. The new administration is also openly debating a renegotiation of the scope of US guarantees within the European security architecture. Analysts are under no illusions. Ian Brzezinski, a former Deputy Assistant Secretary of Defense for Europe and NATO Policy under George W.
Bush, warned in March 2025, in the much-discussed Atlantic Council report 'The Three Seas Initiative stands at an inflection point', co-written with Emma Nix, that the Three Seas must develop its own executive capacity or become a format of no real consequence. In an analysis published five days before the Dubrovnik summit, Brzezinski sharpens this argument: without a permanent secretariat the 3SI will not reach a higher level of effectiveness, and the current investment fund will face a choice between deep restructuring and liquidation.
Niall Ferguson of the Hoover Institution, for his part, draws an analogy with the Suez crisis, arguing that the US strategic turn to other theatres forces Europe to urgently revisit its assumptions about the size of the allied security umbrella.
This has far-reaching consequences for the 3SI states. First, the volatility of US policy decisions weighs on the planning of long-term infrastructure investment. Second, Poland's cohabitation weakens Warsaw's ability to encourage American engagement in the region. Third, Central Europe can no longer treat US guarantees as a given; it must build its own hard resilience, which it did not develop during the 3SI's first decade.
Military planners see the connection clearly. The former Chief of the General Staff of the Polish Armed Forces, General Rajmund Andrzejczak, analysing the conditions of a potential conflict with Russia, points to the need to build a 'northern alliance': the pooling of resources along an axis from Scandinavia to the Black Sea, which geographically coincides with the Three Seas area. General Ben Hodges, former commander of US Army Europe, points out that military logistics ultimately comes down to the parameters of civilian infrastructure: the load capacity of bridges and the capacity of railways. Seen in this light, 3SI projects have as strong a military rationale as a commercial one.
Tasks for Dubrovnik: four key objectives
The Croatian presidency, coordinated by Ambassador Romana Vlahutin (Croatia's national coordinator for the Three Seas Initiative), has set four target areas for decisions at the forthcoming summit. If the meeting is to amount to more than another political declaration, the participating states must take binding decisions on the following issues.
A permanent secretariat. Locating it in Brussels would firmly anchor the format as a structure complementing EU action, give it the legal personality it needs and defuse internal rivalry over political leadership. It would give the Initiative an institutional boost similar to the one the creation of the European External Action Service (EEAS) once gave EU diplomacy.
A Three Seas Development Bank. The Nordic Investment Bank should serve as the reference model. Capital needs to rise from the current EUR 1.1bn or so to EUR 10-15bn; contributions from participating states need to become realistic (reducing the 80% share of Poland's state development bank, BGK, in favour of payments proportionate to the size of each member's economy); and the bank needs to obtain international credit ratings and the right to issue debt instruments.
A fourth pillar: financial architecture. The existing three pillars (transport, energy, digital) define what is to be invested in. The fourth must answer the question of where the money will come from. This requires integrating the mechanisms of the new Development Bank with European funding (through a European Investment Fund (EIF) fund-of-funds) and American funding (DFC), using blended finance models that combine public and private capital.
Regulatory harmonisation. Effective integration formats such as Benelux or the Nordic Council do not stop at building infrastructure; they actively align their legal systems. In its tenth year, the 3SI remains passive in this area. Without harmonised rules in fields such as military mobility, digital sovereignty, the energy transition and the venture capital market, physical infrastructure will not produce a fully integrated regional market, even though some of this alignment takes place within the European Union.
Three scenarios and one boundary condition
As it enters its second decade, the Three Seas Initiative could follow one of three trajectories.
Scenario one: gradual marginalisation. The Dubrovnik summit produces no binding decisions on institutionalisation. The fund grows slowly, relying mainly on Polish capital, strategic investments are delayed further, and the 3SI drifts towards a loose consultative forum, steadily losing geopolitical relevance.
Scenario two: absorption into EU structures. Regional projects are taken over entirely and financed by European Commission instruments. The region gains a stable budgetary framework, but Central European states lose decision-making autonomy and agency in their dealings with external actors (the United States, Japan). The format ceases to be an effective asset in diplomatic negotiations.
Scenario three: full institutionalisation. The summit decides to establish a general secretariat and a regional development bank. Within five years the fund is recapitalised to EUR 15bn, or replaced by a new structure of that scale if the current 3SIIF is deemed exhausted. Work on the main corridors accelerates dramatically, and after 2032 Ukraine joins the Initiative as a full participant. This scenario, however, requires unwavering political will from all thirteen participating states, going beyond diplomatic practice to date.
All these trajectories share one structural common denominator. Until the format's funding system changes radically, the Three Seas will remain, in essence, a Polish project with merely political backing from the other capitals. A model in which a country generating 25% of regional GDP covers 80% of capital costs and serves as the Initiative's main driving force is unsustainable in the long run. Together, the thirteen 3SI states potentially form the world's seventh-largest economy, and a macro-region of that kind must base its development on proportionality and shared financial responsibility.
The first decade made it possible to define a community of interests and to develop the beginnings of financial instruments. The second will determine whether Central Europe creates a mechanism capable of turning those interests into hard geopolitical facts. In international relations, structures that are not institutionalised in their first decade rarely manage it later, because the political cost of doing so rises every year.
The Dubrovnik summit will therefore shape not only the future of the Three Seas Initiative itself, but also answer the question of whether Central Europe has a genuine capacity to shape its own economic agency through cooperation, or whether it remains a space in which that agency is dictated by external conditions.
