[2] In June 2018, prior to the B9 meeting that year, President of Poland Andrzej Duda spoke out in favour of Ukrainian and Georgian NATO membership ambitions.

[4] On 10 May 2021, during a B9 video conference summit which the President of the United States Joe Biden joined, President of Romania Klaus Iohannis (one of the two hosts of the summit, the other being Duda) called for "stronger allied military presence [...] on the bloc's eastern flank" following the mobilization of Russian troops near the Russian border with Ukraine which had happened some time before.

[5] On 25 February 2022, the B9 group with the addition of Ursula von der Leyen, President of the European Commission, gathered in light of the 2022 Russian invasion of Ukraine.

Duda added that a brigade group has 3,000 troops, which would mean a "significant and visible strengthening",[9] while Iohannis said that "NATO must be capable to defend every inch of its territory".

[12] At a summit on 22 February 2023, the heads of state of the Bucharest Nine countries, as well as Biden and Stoltenberg, signed a declaration which issued a condemnation of the Russian invasion of Ukraine and called for an enhanced military presence of NATO on the eastern flank of the alliance.