On February 11, 2019, a meeting of Polish President Andrzej Duda was held in Warsaw's presidential palace, with Ambassadors accredited in the Polish capital of the Three Seas Initiative and US Ambassadors of the same countries. Bulgaria was represented by Ambassador Emil Yalnazov. On the same day at the US Embassy in Warsaw, on the initiative of Ambassador J. Mossbacher, a working seminar of the US Ambassadors accredited in the States participating in the Initiative was held, including the US Ambassador to Sofia, Mr. Eric Rubin. The Warsaw Ambassadorial Forum was organized with the assistance of the Atlantic Council of the United States.

In his address to the participants, President Duda underscored the unique nature of the Three Seas initiative, bringing together the participating countries around the common goal of developing energy infrastructure, transport connectivity, communications and the digital economy through the implementation of priority projects in these areas. Through improved economic co-operation and connectivity, the initiative contributes to the overall security and prosperity of citizens in the region. It is in line with convergence and cohesion policies within the EU as it leads to a more efficient spending of EU funds and alignment of standards in the key areas above between the old and new EU members.

President Duda also highlighted the great importance of US and President Donald Trump's support for this initiative, jointly launched by Poland and Croatia in 2016. He expressed hope that the Three Seas Investment Fund will become operational in the near future, , which aims to provide the necessary funding for key infrastructure projects of regional significance. The President wished Slovenia to host the next Summit of the initiative, to be held in Ljubljana on June 5-6 of this year.