U.S. President Joe Biden will join a meeting by video link of presidents of countries on NATO's eastern flank being held Monday in the Romanian capital, according to the offices of the Romanian and Polish presidents.
The presidents gathering represent the so-called Bucharest Nine, a group of the easternmost members of the Western military alliance. Most of them share a concern about Russia's attempts to reassert its influence over their region, their anxieties growing after Russia annexed Ukraine's Crimean Peninsula in 2014.
Romanian President Klaus Iohannis, the host, said on Twitter that he was glad to be welcoming Biden, and that the meeting was in preparation for a full NATO summit next month.
He said Monday's meeting, co-hosted by Polish President Andrzej Duda, would include discussions of defense and deterrence on the alliance's Eastern flank, and that NATO Secretary General Jens Stoltenberg was also participating.
The head of Poland's National Security Bureau, Pawel Soloch, said that security in the Black Sea region and in Ukraine would also be under discussion.
Those in the Bucharest nine are Romania, Poland, Hungary, Bulgaria, the Czech Republic, Slovakia, and the three small Baltic states of Estonia, Latvia and Lithuania.
These countries were all controlled by Moscow during the cold war, with the Baltic states incorporated into the Soviet Union. Today they are all members of NATO and the Europe Union.
The meeting of the nine comes ahead of a NATO summit taking place June 14 in Brussels, where the alliance has its headquarters.
At the June summit, Biden and other leaders plan to discuss tense ties with Russia and China, the troop withdrawal from Afghanistan and the future of the 30-nation alliance.