Timeline of NATO expansion since 1949

FILE - Top generals of the Warsaw Treaty shake hands during a meeting in Moscow, Soviet Union, Monday March 25, 1991. From left to right: Rumanian Mircea Constantinescu; Bulgarian Penyu Kostadinov; Soviet General Vladimir Lyubov; Hungarian Robert Seles; and Czech Michal Gondech, met for the last time, as the treaty will be dissolved March 31, 1991. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/File)

Timeline of NATO expansion since 1949