Turning from 3 to 4 Seas – Greece’s Gamble on 3SI
Mihai Christopher Marian Radovici
3SI’s transformation from a CEE cooperation framework into a broader regional platform reached a pivotal moment with Greece’s accession as its 13th member during the 2023 Bucharest Summit. This expansion, which literally added a fourth sea to the initiative’s geographic scope, represents more than symbolic growth, it signals a strategic recalibration that has proven mutually beneficial for both Athens and the evolving regional architecture.
During the Bucharest Summit in September 2023, the Three Seas Initiative’s (3SI) coastline drastically increased due to Athens’ accession [1], a momentum that altered its pragmatic and paradigmatic scope. Thereafter, Greece’s adhesion alongside Ukraine and Moldova’s associate partnership status tested 3SI’s capacity to accommodate diverse regional perspectives and maintain operational coherence [2]. The grander structure now encompasses 13 EU members and spans from the Baltic to the Mediterranean, or roughly 28% of EU territory and 22% of its population [3].
Establishing a brand in the international arena
Whereas its geopolitical weight was increased by interlinking four seas, the new neighbourhood surfaced a plethora of challenges and opportunities alike. One of the most tangible manifestation emerging was the Via Carpathia project (submitted by Romania), where Greece serves as the southern terminus (Thessaloniki) for a major transnational highway reaching into Lithuania (Klaipėda) [4]. Set soon to be completed, the initiative transcends what was a CEE corridor into a pan-European transit artery, regardless of the economic disparities that slowed progress.
Otherwise, the Hellenic involvement enabled 3SI to spearhead its North-South corridor narrative towards the Mediterranean and MENA regions, evidenced by Innovation Fund’s 2024 launch (under EIF’s aegis), with Polish BGK and Czech NRI pledging from the get-go €20 million each [5]. Moreover, US International Development Finance Corporation’s confirmation of its $300 million investment commitment to the Three Seas Investment Fund [6] demonstrates growing international confidence in the expanded Initiative and showcases real growth potential.
However, Athens’ complex regional relationships, particularly ongoing tensions with Ankara and the delicate North Macedonia situation, translates into new diplomatic variables that need to be addressed; especially delicate since 3SI lacked in the past political determinism [7]. This complexity became evident during 2024 summit discussions on regional security cooperation, where Greece’s Mediterranean security concerns required careful balancing against Baltic and Central European priorities focused on eastern threats.
Similarly, 3SI’s business credentials evolved substantially since the expansion, as the 48 priority interconnection projects [8] took new dimensions, with Greek ports and energy systems providing southern anchoring points. Also, the Investment Fund, set to raise 3-5 billion EUR from private investors, benefited from Athens’ financial networks and southern market access, though the Hellenic financial profile and recent recovery trajectory introduced new risk considerations [9].
„Our country’s accession to the Initiative offers the opportunity to monitor processes within a large grouping of EU member states... It is considered mutually beneficial for both the Initiative and our country, as it allows the expansion of the geopolitical footprint of the 3SI and the projects of interconnectivity it envisions, not only in the Mediterranean and Aegean but also more broadly in North Africa and Middle East region.” – Hellenic Republic Ministry of Foreign Affairs, speech made by its representatives at the 2023 Bucharest Summit.
The rationale from Pantheon
Recent evolutions have vindicated Athens’ strategic calculus while unravelling the challenge of integrating a Mediterranean member into a continental framework. Thus, Greece’s positioning as an energy hub materialised through the transformation of Alexandroupolis Port [10] into a critical dual-use facility serving both civilian logistics and NATO military coordination. Also, the country’s updated National Energy and Climate Plan [11] submitted to the EU in 2024 reflects ambitious renewable energy targets aligning with 3SI sustainability objectives, while highlighting different starting points across member states. Yet, Athens’ advanced offshore renewable energy sector and Mediterranean solar potential provide new technological dimensions, though integrating the North-South grids require unprecedented coordination.
The Greek government’s ability to bypass Brussels’ complex mechanisms through direct 3SI engagement has facilitated several bilateral energy agreements, particularly regarding LNG cooperation and pipeline coordination [12] with Bulgaria and Albania. However, this approach clashed with the European Commission’s preferences for centralised coordination.
Nonetheless, Greece’s established role in Mediterranean security has particularly benefited NATO-3SI cooperation. The 2024 Joint Declaration emphasised commitment to regional cyber resilience and cybersecurity infrastructure, areas where Greece’s experience with hybrid threats provides valuable expertise to northern partners [13].
Obstacles, opportunities and in-betweens
The 2025 Warsaw Summit, marking the Initiative’s 10th anniversary, represents a critical moment for addressing institutional maturity challenges [14], some of which were increased by the southern expansion [15]. Also, Athens’ complex regional relationships complicate consensus-building, as the fundamental challenge lies in expansion occurring before establishing permanent institutions and clear administrative norms. Hence, the current system of rotating presidencies has proven inadequate [16] for managing diverse priorities when it comes to divergent members, especially as all decisions are point-by-point negotiated and remain informal.
Running alongside Ukraine and Moldova’s rapprochement, as associate partners, Athens’ integration, albeit requiring careful managing, provided 3SI with unprecedented strategic depth and connectivity, turning it into a genuinely continental forum. In this regard, Ukraine’s associate partnership, confirmed in late 2023 alongside Moldova’s similar status [17], creates European integration pathways that Greece’s successful integration helps legitimise. Albeit the fact that growing financial instruments provide transformational foundations and raise burden-sharing questions across all members, Athens’ somewhat problematic economy highlights deeply rooted inclusion disparities.
Looking toward the 2025 landmark, Greece’s role in driving 3SI revitalisation appears increasingly likely as the country’s positioning as bridge between the European core and periphery provides strategic options extending far beyond original conception. However, realising this potential requires institutional adaptations accommodating southern perspectives while maintaining CEE identity and effectiveness.
Photo source: PxHere.com.
Notes:
[1] Notes from Poland (2023) ‘Greece becomes 13th member of Three Seas Initiative on EU’s eastern flank’, Notes from Poland, 7 September. Available at: https://notesfrompoland.com/2023/09/07/greece-becomes-13th-member-of-three-seas-initiative-on-eus-eastern-flank/
[2] Atlantic Council (2023) The Three Seas Initiative stands at an inflection point. Washington, DC: Atlantic Council. Available at: https://www.atlanticcouncil.org/in-depth-research-reports/issue-brief/the-three-seas-initiative-stands-at-an-inflection-point/
[3] Three Seas Initiative (n.d.) The Three Seas Initiative. E-book. Available at: https://media.voog.com/0000/0046/4166/files/The%20Three%20Seas%20Initiative%20ebook.pdf
[4] Three Seas Initiative (n.d.) Via Carpatia project (submitted by Romania). Available at: https://projects.3seas.eu/projects/via-carpatia-submitted-by-romania
[5] European Investment Fund (2024) ‘Central and Eastern Europe’s growth-stage companies get boost as Polish and Czech promotional institutions become first contributors to EIF-led Three Seas Initiative Innovation Fund’. Available at: https://www.eif.org/what_we_do/equity/news/2024/central-and-eastern-europes-growth-stage-companies-get-boost-as-polish-and-czech-promotional-institutions-become-first-contributors-to-eif-led-three-seas-initiative-innovation-fund.htm
[6] Three Seas Initiative (n.d.) ‘U.S. International Development Finance Corporation and the Three Seas Initiative Investment Fund agree to term sheet for up to USD 300 million in financing’. Available at: https://3seas.eu/media/news/u-s-international-development-finance-corporation-and-the-three-seas-initiative-investment-fund-agree-to-term-sheet-for-up-to-ususd300-million-in-financing
[7] DipAM – Diplomatic Affairs Magazine (n.d.) Regionalization in Europe: The transformation of the Three Seas Initiative. Available at: https://en.dipam.org/regionalization-in-europe-the-transformation-of-the-three-seas-initiative/
[8] Three Seas Initiative (n.d.) Progress Report. Available at: https://3seas.eu/about/progressreport
[9] European Commission (n.d.) National Energy and Climate Plans. Available at: https://commission.europa.eu/energy-climate-change-environment/implementation-eu-countries/energy-and-climate-governance-and-reporting/national-energy-and-climate-plans_en
[10] Ports Europe (n.d.) Port of Alexandroupouli. Available at: https://www.portseurope.com/category/ports/alexandropouli/
[11] International Energy Agency (2024) National Energy and Climate Plan (NECP) update 2024. Available at: https://www.iea.org/policies/28634-national-energy-and-climate-plan-necp-update-2024
[12] International Trade Administration (2024) Greece renewable energy projects 2024. Washington, DC: U.S. Department of Commerce. Available at: https://www.trade.gov/market-intelligence/greece-renewable-energy-projects-2024
[13] Three Seas Initiative (2023) Joint declaration of the eighth summit of the Three Seas Initiative. Available at: https://3seas.eu/media/joint-declaration-of-the-eighth-summit-of-the-three-seas-initiative
[14] Institute of New Europe (2025) The Three Seas Initiative in 2025: On the road to its anniversary. Available at: https://ine.org.pl/en/the-three-seas-initiative-in-2025-on-the-road-to-its-anniversary/
[15] Institute of New Europe (n.d.) Three Seas Initiative. Available at: https://ine.org.pl/threeseasinitiative/
[16] GIS Reports Online (n.d.) Three Seas Initiative. Available at: https://www.gisreportsonline.com/r/three-seas-initiative-3/
[17] Drăgulin, G. (n.d.) The Three Seas Initiative. Bucharest: Institutul Diplomatic Român. Available at: https://www.idr.ro/publicatii/Dr%C4%83gulin_PB78_EN.pdf
