The Three Seas Initiative (3SI or TSI), known also as the Baltic, Adriatic, Black Sea (BABS) Initiative or simply as the Three Seas (

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

: ''Trimarium'', ), is a forum of thirteen states, in the

European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...

, running along a north–south axis from the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

to the

Adriatic The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkans, Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Se ...

and

Black Sea The Black Sea is a marginal sea, marginal Mediterranean sea (oceanography), mediterranean sea lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bound ...

s in

Central and Eastern Europe Central and Eastern Europe is a geopolitical term encompassing the countries in Baltic region, Northeast Europe (primarily the Baltic states, Baltics), Central Europe (primarily the Visegrád Group), Eastern Europe, and Southeast Europe (primaril ...

. The Initiative aims to create a regional dialogue on questions affecting the member states. In 2016, representatives of the original 12 member states (

Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

Croatia Croatia, officially the Republic of Croatia, is a country in Central Europe, Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herze ...

, the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

Estonia Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Ru ...

Hungary Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...

Latvia Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to t ...

Lithuania Lithuania, officially the Republic of Lithuania, is a country in the Baltic region of Europe. It is one of three Baltic states and lies on the eastern shore of the Baltic Sea, bordered by Latvia to the north, Belarus to the east and south, P ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

Slovakia Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the west, and the Czech Republic to the northwest. Slovakia's m ...

, and

Slovenia Slovenia, officially the Republic of Slovenia, is a country in Central Europe. It borders Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the south and southeast, and a short (46.6 km) coastline within the Adriati ...

) met for their first summit in

Dubrovnik Dubrovnik, historically known as Ragusa, is a city in southern Dalmatia, Croatia, by the Adriatic Sea. It is one of the most prominent tourist destinations in the Mediterranean Sea, Mediterranean, a Port, seaport and the centre of the Dubrovni ...

, Croatia. At the seventh summit in

Riga Riga ( ) is the capital, Primate city, primate, and List of cities and towns in Latvia, largest city of Latvia. Home to 591,882 inhabitants (as of 2025), the city accounts for a third of Latvia's total population. The population of Riga Planni ...

on 20 June 2022,

Ukraine Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...

received the status of a partner-participant of the TSI, '' de facto'' becoming a participant in this initiative. At the 2023 summit,

Greece Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...

became a member and

Moldova Moldova, officially the Republic of Moldova, is a Landlocked country, landlocked country in Eastern Europe, with an area of and population of 2.42 million. Moldova is bordered by Romania to the west and Ukraine to the north, east, and south. ...

a partner-participant, while at the 2025 summit,

Albania Albania ( ; or ), officially the Republic of Albania (), is a country in Southeast Europe. It is located in the Balkans, on the Adriatic Sea, Adriatic and Ionian Seas within the Mediterranean Sea, and shares land borders with Montenegro to ...

and

Montenegro , image_flag = Flag of Montenegro.svg , image_coat = Coat of arms of Montenegro.svg , coa_size = 80 , national_motto = , national_anthem = () , image_map = Europe-Mont ...

became partner-participants.

Statistics

The twelve Three Seas countries cover 29 per cent of the

's territory (), are home to 25 percent of the European Union's inhabitants (110million), and produce €2.3trillion or one seventh of the EU's GDP (nominal).

History

The Three Seas Initiative, which was influenced by the Polish

interwar In the history of the 20th century, the interwar period, also known as the interbellum (), lasted from 11 November 1918 to 1 September 1939 (20 years, 9 months, 21 days) – from the end of World War I (WWI) to the beginning of World War II ( ...

Intermarium concept, was launched in 2015 by Polish President

Andrzej Duda Andrzej Sebastian Duda (born 16 May 1972) is a Polish lawyer and politician who has served as the sixth president of Poland since 2015. Before becoming president, he served as a Member of the Sejm from 2011 to 2014 and before becoming Member of ...

and Croatian President Kolinda Grabar-Kitarović.

First summit, Dubrovnik, 2016

The Initiative's first summit, held in

, Croatia, on 25–26 August 2016, ended with a declaration of economic cooperation in energy and in transport and communications infrastructures. Polish President

called the initiative "a new concept to promote Europe's unity and cohesion... an idea of cooperation among 12 countries located between the Adriatic, Baltic and Black Seas, the three seas of Central Europe." Guests included Chinese Ministerial Assistant for Foreign Affairs Liu Haixing, who spoke about Three Seas Initiative interconnectedness with China's

Belt and Road Initiative The Belt and Road Initiative (BRI or B&R), known in China as the One Belt One Road and sometimes referred to as the New Silk Road, is a global infrastructure development strategy adopted by the government of China in 2013 to invest in more t ...

, and former US National Security Advisor General James L. Jones, who stressed the Three Seas Initiative's role in European development and security.

Second summit, Warsaw, 2017

The Initiative's second summit was held 6–7 July 2017 in

Warsaw Warsaw, officially the Capital City of Warsaw, is the capital and List of cities and towns in Poland, largest city of Poland. The metropolis stands on the Vistula, River Vistula in east-central Poland. Its population is officially estimated at ...

, Poland. Guest attendees included US President

Donald Trump Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who is the 47th president of the United States. A member of the Republican Party (United States), Republican Party, he served as the 45 ...

. The participating countries unanimously agreed to set up a Three Seas Business Forum.

Third summit, Bucharest, 2018

The Initiative's third summit took place 17–18 September 2018 in

Bucharest Bucharest ( , ; ) is the capital and largest city of Romania. The metropolis stands on the River Dâmbovița (river), Dâmbovița in south-eastern Romania. Its population is officially estimated at 1.76 million residents within a greater Buc ...

, Romania. Participants approved interconnection projects in three key areas: transport, energy, and digital. Guest attendees included President of the European Commission

Jean-Claude Juncker Jean-Claude Juncker (; born 9 December 1954) is a Luxembourgish politician who was List of prime ministers of Luxembourg, prime minister of Luxembourg from 1995 to 2013 and president of the European Commission from 2014 to 2019. He also was List ...

, German Foreign Minister

Heiko Maas Heiko Josef Maas (; born 19 September 1966) is a German lawyerMarcus Jung (15 December 2022)�''Frankfurter Allgemeine Zeitung''. and former politician of the Social Democratic Party of Germany, Social Democratic Party (SPD) who served as the Mini ...

, and US Secretary of Energy

Rick Perry James Richard Perry (born March 4, 1950) is an American politician who served as the 14th United States secretary of energy from 2017 to 2019 in the first administration of Donald Trump. He previously served as the 47th governor of Texas fr ...

. The first edition of the Business Forum was organised. A 3SI Network of Chambers of Commerce was created, and a

letter of intent A letter of intent (LOI or LoI, or Letter of Intent) is a document outlining the understanding between two or more parties which they intend to formalize in a legally binding agreement. The concept is similar to a heads of agreement, term she ...

was signed concerning establishment of a Three Seas Investment Fund.

List of summits

Projects

The initiative is closely related to two major infrastructure projects in the region: * A north–south highway " Via Carpathia", connecting

Klaipėda Klaipėda ( ; ) is a city in Lithuania on the Baltic Sea coast. It is the List of cities in Lithuania, third-largest city in Lithuania, the List of cities in the Baltic states by population, fifth-largest city in the Baltic States, and the capi ...

in Lithuania with

Thessaloniki Thessaloniki (; ), also known as Thessalonica (), Saloniki, Salonika, or Salonica (), is the second-largest city in Greece (with slightly over one million inhabitants in its Thessaloniki metropolitan area, metropolitan area) and the capital cit ...

Liquefied natural gas Liquefied natural gas (LNG) is natural gas (predominantly methane, CH4, with some mixture of ethane, C2H6) that has been cooled to liquid form for ease and safety of non-pressurized storage or transport. It takes up about 1/600th the volume o ...

infrastructure, with sea terminals in Poland and Croatia and a connecting pipeline Other projects are the Baltic-Adriatic Corridor, Via Baltica road, Rail Baltica and Amber Rail Freight Corridor rail connections. Another project is Rail-2-Sea, which aims to connect the Baltic Sea port of

Gdańsk Gdańsk is a city on the Baltic Sea, Baltic coast of northern Poland, and the capital of the Pomeranian Voivodeship. With a population of 486,492, Data for territorial unit 2261000. it is Poland's sixth-largest city and principal seaport. Gdań ...

(Poland) with the Black Sea port of

Constanța Constanța (, , ) is a city in the Dobruja Historical regions of Romania, historical region of Romania. A port city, it is the capital of Constanța County and the country's Cities in Romania, fourth largest city and principal port on the Black ...

(Romania) through a long railway line.

Three Seas Initiative Investment Fund (3SIIF)

The initial two founding institutions from Poland and Romania have committed themselves to make payments totaling more than 500 million euros. The Fund is open to other Three Seas countries, which may join it after obtaining appropriate permits. The supervisory board of the Fund consists of representatives of development banks from Poland, Romania, Latvia, and the Czech Republic. In 2019,

Bank Gospodarstwa Krajowego The National Development Bank (Polish language, Polish: ''Bank Gospodarstwa Krajowego'', BGK) is a Polish national development bank with headquarters in Warsaw, is a state-owned bank in Poland, operating under a dedicated bill of law. Its main ta ...

and Export–Import Bank of Romania signed the founding act of the Three Seas Initiative Investment Fund. The fund is to focus on projects creating transport, energy and digital infrastructure in the Three Seas region. Private investors from

pension fund A pension fund, also known as a superannuation fund in some countries, is any program, fund, or scheme which provides pension, retirement income. The U.S. Government's Social Security Trust Fund, which oversees $2.57 trillion in assets, is the ...

s, private investment funds, and other entities will also be invited to the fund. The aim is to raise up to €3–5 billion. The fund will engage, on a commercial basis, in infrastructure projects with a total value of up to €100 billion, while the needs of the Three Seas region have been estimated at over €570 billion. Prior to the 2020 Tallinn Summit,

United States Secretary of State The United States secretary of state (SecState) is a member of the executive branch of the federal government of the United States and the head of the U.S. Department of State. The secretary of state serves as the principal advisor to the ...

Mike Pompeo Michael Richard Pompeo (; born December 30, 1963) is an American retired politician who served in the First presidency of Donald Trump#Administration, first administration of Donald Trump as director of the Central Intelligence Agency (CIA) fr ...

pledged up to a billion dollars in financing for the Investment Fund. The investment was not made. The fund's assets were estimated at €900 mil. in 2023. The fund is collaborating with the Amber Infrastructure Group in raising capital and managing investments.

Perception

Croatia

Social-democratic Croatian President

Zoran Milanović Zoran Milanović (; born 30 October 1966) is a Croatia, Croatian politician and the incumbent president of Croatia. First elected in 2020, he was re-elected in 2025 with 74% voter support. Prior to assuming the presidency, he was the prime min ...

stated that the initiative is harmful for

Czech Republic

The Three Seas Initiative was perceived rather negatively by

Czech Czech may refer to: * Anything from or related to the Czech Republic, a country in Europe ** Czech language ** Czechs, the people of the area ** Czech culture ** Czech cuisine * One of three mythical brothers, Lech, Czech, and Rus *Czech (surnam ...

experts and diplomats during its launch. It was seen as a Polish attempt to create its

sphere of influence In the field of international relations, a sphere of influence (SOI) is a spatial region or concept division over which a state or organization has a level of cultural, economic, military, or political exclusivity. While there may be a formal a ...

(similar to the historical perception of Intermarium). Further fears were related to a possibility of deepening the east–west division in the EU and exclusion of

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

. A long term Czech objection was that there should be no competing geopolitical project in the region that would weaken the EU. Some of those objections have been partially addressed lately also due to a good experience with cooperation on infrastructure projects in the

Visegrád Group The Visegrád Group (also known as the Visegrád Four or the V4) is a cultural and political alliance of four Central European countries: the Czech Republic, Hungary, Poland, and Slovakia. The alliance aims to advance co-operation in military, e ...

. Further improvement of Czech position toward the Initiative happened after the term of the president

Miloš Zeman Miloš Zeman (; born 28 September 1944) is a Czech politician who served as the third president of the Czech Republic from 2013 to 2023. He also previously served as the prime minister of the Czech Republic from 1998 to 2002. As leader of the Cze ...

ended and the government could remove from the Czech priority list the controversial project of Danube-Odra-Labe channel in 2023. The Ministry of foreign affairs suggested the new priority projects should be the gas connection STORK II and

high-speed rail High-speed rail (HSR) is a type of rail transport network utilising trains that run significantly faster than those of traditional rail, using an integrated system of specialised rolling stock and dedicated railway track, tracks. While there is ...

connection to Poland. On the other hand, Czechia still does not seem interested in joining the Investment fund or hosting a summit.

Finland

The populist

Finns Party The Finns Party ( , PS; , Sannf), formerly known as the True Finns, is a right-wing populist political party in Finland. It was founded in 1995 following the dissolution of the Finnish Rural Party. The party achieved its electoral breakthro ...

has advocated for

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

to join the initiative.

Ukraine

In 2016, Ukraine was sent an invitation to the Three Seas Summit in Dubrovnik. However, no state representative was sent to the meeting. In August 2019, during the visit of

Ukrainian President The president of Ukraine (, ) is the head of state of Ukraine. The president represents the nation in international relations, administers the foreign political activity of the state, conducts negotiations and concludes international treaties. ...

Volodymyr Zelenskyy Volodymyr Oleksandrovych Zelenskyy (born 25 January 1978) is a Ukrainian politician and former entertainer who has served as the sixth and current president of Ukraine since 2019. He took office five years after the start of the Russo-Ukraini ...

, he stated that Ukraine is interested in becoming an active participant in regional projects and initiatives in Poland, such as the Three Seas, which covers the

Baltic Baltic may refer to: Peoples and languages *Baltic languages, a subfamily of Indo-European languages, including Lithuanian, Latvian and extinct Old Prussian *Balts (or Baltic peoples), ethnic groups speaking the Baltic languages and/or originatin ...

and

Black Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness.Eva Heller, ''P ...

Seas. It was also noted that Ukraine is already cooperating in the construction of the trans-European Via Carpatia highway, and is discussing an ambitious E-40 waterway project for Ukraine." In October 2019, Polish Foreign Minister Jacek Czaputowicz said that Ukraine could not now join the Three Seas Initiative, as it includes the countries of Central and

Southern Europe Southern Europe is also known as Mediterranean Europe, as its geography is marked by the Mediterranean Sea. Definitions of southern Europe include some or all of these countries and regions: Albania, Andorra, Bosnia and Herzegovina, Bulgaria, C ...

, which are members of the

. The head of Polish diplomacy explained that the Three Seas Initiative should not be associated with

geopolitics Geopolitics () is the study of the effects of Earth's geography on politics and international relations. Geopolitics usually refers to countries and relations between them, it may also focus on two other kinds of State (polity), states: ''de fac ...

, as it is only an infrastructure project. In November 2019, during the visit of the

President of Ukraine The president of Ukraine (, ) is the head of state of Ukraine. The president represents the nation in international relations, administers the foreign political activity of the state, conducts negotiations and concludes international treaties. ...

, he stated that Ukraine is interested in joining the TSI and intends to discuss this issue with Estonian partners. After the start of the 2022 Russian invasion during the

Russian-Ukrainian War The Russo-Ukrainian War began in February 2014 and is ongoing. Following Ukraine's Revolution of Dignity, Russia Russian occupation of Crimea, occupied and Annexation of Crimea by the Russian Federation, annexed Crimea from Ukraine. It then ...

President of Poland The president of Poland ( ), officially the president of the Republic of Poland (), is the head of state of Poland. His or her prerogatives and duties are determined in the Constitution of Poland. The president jointly exercises the executive ...

in his address to the

Verkhovna Rada of Ukraine The Verkhovna Rada ( ; VR), officially the Verkhovna Rada of Ukraine, is the unicameralism, unicameral parliament of Ukraine. It consists of 450 Deputy (legislator), deputies presided over by a speaker. The Verkhovna Rada meets in the Verkhovn ...

on 22 May 2022, stated that Ukraine should join the Three Seas Initiative. Later, on 7 June 2022, the

Prime Minister of Poland A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only wa ...

Mateusz Morawiecki Mateusz Jakub Morawiecki (; born 20 June 1968) is a Polish economist, historian and politician who served as the prime minister of Poland between 2017 and 2023. A member of the Law and Justice (PiS) party, he previously served in the Cabinet of ...

, at the opening of a two-day congress of local self-government in the Three Seas in

Lublin Lublin is List of cities and towns in Poland, the ninth-largest city in Poland and the second-largest city of historical Lesser Poland. It is the capital and the centre of Lublin Voivodeship with a population of 336,339 (December 2021). Lublin i ...

, stated that the Three Seas Initiative is impossible without involving a free and sovereign

. At the seventh summit in

on 20 June 2022, speaking on video, the

stated that

should become a member of the Three Seas Initiative. Zelenskyy suggested strengthening the interpretation of cooperation within the Three Seas, emphasizing the importance of logistics. Speaking about cooperation in the energy sector, Zelenskyy reminded that Ukraine has one of the largest gas storage facilities in the region. At this summit Ukraine received the status of a partner-participant of the TSI, '' de facto'' becoming a participant in this initiative.

References

External links

2020 Official website

2019 Official website

2018 Official website
{{Regional organizations Central Europe Eastern Europe European integration International economic organizations International political organizations International security Foreign relations of Lithuania Central European intergovernmental organizations 2015 establishments in Europe Intermarium Bottom-up regional groups within the European Union Organizations established in 2015 First presidency of Donald Trump