On August 21, 2023, the Prime Minister Nikolay Denkov took part in an informal dinner in Athens, held on the initiative of the Greek Prime Minister Kyriakos Mitsotakis, of leaders of Western Balkan countries (Bosnia and Herzegovina, Kosovo, the Republic of North Macedonia, Serbia, Montenegro), the Prime Ministers of Bulgaria, Romania and Croatia, the Presidents of Ukraine and Moldova and the Presidents of the European Commission and the European Council.

The event marks the 20th anniversary of the adoption of the Thessaloniki Agenda, which opened the way for the Balkans to the European Union. The informal meeting concluded with the adoption of the Athens Declaration condemning Russian aggression in Ukraine and expressing support for Ukraine’s independence, sovereignty and territorial integrity within its internationally recognized borders, as well as for achieving sustainable peace based on President Zelensky's Peace Formula. It is emphasized that the future of the Western Balkans, Ukraine and Moldova is in the EU, and as a strategic investment in peace, security and stability in Europe, it is important that these regions are accepted as full members of the European family.

During his visit to Athens, Prime Minister Denkov held bilateral meetings with the President of Moldova, Maya Sandu, the President of Ukraine, Volodymyr Zelensky, and with the Prime Minister of Romania, Ion-Marcel Ciolacu.