The biggest change in the operation of the format is the addition of a new member - Greece. According to the declaration, the expansion of the 3SI format to include Greece is expected to strengthen the Initiative and create new opportunities for economic development and the construction of north-south transport, energy and digital infrastructure, as well as improve cohesion within the European Union. Greece, on whose territory some of the transport routes of the projects presented under the Initiative end, infrastructurally closes off its territory to the south.

Indeed, the Via Carpatia route leading from Lithuania's Klaipeda is to end in Thessaloniki, while Greek LNG terminals, including those in Alexandroupolis, are expected to enable more effective diversification of LNG sources through the expansion of north-south gas connections.

The addition of Greece as the thirteenth country confirms the exclusive nature of the Initiative, co-created only by EU countries. It also makes obsolete the narrative about the Initiative as an association of countries that – with the exception of Austria – joined the EU since 2004.

This year, Ukraine and Moldova obtained the status of an associated country, which allows them to participate in the Initiative's activities, including projects. In a joint declaration, the members of the Initiative again condemned Russia's aggression, emphasizing the need to withdraw its forces from Ukrainian territory. At the same time, they declared their participation in the reconstruction of Ukraine and their efforts for this purpose at the EU and international level. Another opportunity to remind about the impact of the war on the regional debate was the remote speech of the President of Ukraine, Volodymyr Zelensky.

The Three Seas Initiative remains a form focused on the development of regional infrastructure. Although the Three Seas countries spent EUR 80 billion on infrastructure projects in 2018–2021, mainly national priorities and EU funds were taken into account. Therefore, in order to make the initiative credible, it is necessary to increase the dynamics of the development of infrastructure connections created thanks to its support. To achieve this, it is necessary to involve both the private sector and the Member States (the Czech Republic, Slovakia and Austria are still refraining from joining the Three Seas Fund). The willingness to abandon the import of Russian raw materials increases the potential importance of energy cooperation under the Initiative.

The Bucharest Summit is also characterized by the broad participation of partners such as the European Bank for Reconstruction and Development, the European Commission, the World Bank and the International Monetary Fund. For the first time, representatives of Japan, France, Great Britain and Turkey took part in the discussions. After the summit, the Three Seas Initiative Business Forum was held for the fifth time. Evidence of the institutionalization of the Three Seas Initiative was the announcement of the establishment of an association of entrepreneurs and employers that would represent their interests, among others at the request of Poland, Bulgaria, Lithuania and Romania before the EU institutions. The establishment of the Three Seas Innovation Fund, the second financial instrument of the Initiative, was also announced.

To sum up, this year's Three Seas Initiative Summit in Bucharest brought many important changes to the initiative and confirmed that Romania intends to play a central role in this format. This is good news, especially for Poland, which has so far shown the greatest commitment as the largest country in the region and the founder of the initiative. In many other countries, participation is low but increases with each summit, either because of changing political priorities or because companies in a given country are increasingly interested in regional business opportunities.

Lithuania took over the presidency of the Three Seas Initiative from Romania and will host the next summit and business forum in 2024.