The April 2026 edition of the IRMO Brief, authored by Adam Chmielecki, deals with the Three Seas Initiative (3SI) which was born in 2015, as a result of a meeting between the then presidents of Poland and Croatia, Andrzej Duda and Kolinda Grabar -Kitarović on sidelines of the UN summit in New York, supported by the US administration. The current 13 member states of the 3SI represent a market of 121 million inhabitants or 26% of the EU, while also accounting for 30% of the EU’s territory and 17% of its GDP. 3SI is an example of regional cooperation that emphasizes the principle of subsidiarity, which is still in force in the EU. In Poland, the 3SI is widely recognized as one the greatest successes of President Andrzej Duda’s presidency, alongside with the Polish membership in NATO. The author also analyses how the 3SI has demonstrated that Europe needs to develop along a North-South axis, from the Nordic countries to Greece and Turkey, with Central Europe as the keystone.
The Three Seas Initiative Between the First and Second Decades: Political Context in Poland
