NATO
New membership in the alliance has been largely from Central and Eastern Europe, including former members of the Warsaw Pact. Accession to the alliance is governed with individual Membership Action Plans, and requires approval by each current member. NATO currently has two candidate countries that are in the process of joining the alliance: Bosnia and Herzegovina and the Republic of Macedonia.
In NATO official statements, the Republic of Macedonia is always referred to as the "former Yugoslav Republic of Macedonia", with a footnote stating that "Turkey recognizes the Republic of Macedonia under its constitutional name". Though Macedonia completed its requirements for membership at the same time as Croatia and Albania, who joined NATO in 2009, its accession was blocked by Greece pending a resolution of the Macedonia naming dispute. In order to support each other in the process, new and potential members in the region formed the Adriatic Charter in 2003. Georgia was also named as an aspiring member, and was promised "future membership" during the 2008 summit in Bucharest, though in 2014, US President Barack Obama said the country was not "currently on a path" to membership.
Foreign policy of Vladimir Putin
The Baltic states of Estonia, Lithuania, and Latvia—all three of which are members of NATO—have warily watched Russian military movements and actions. All three countries, within the Russian Empire prior to 1918, had been annexed by the Soviet Union in 1940 as part of the Molotov–Ribbentrop Pact, and Russian leaders were particularly distressed by their accession to NATO and the EU in 2004. In 2014, the Baltic states reported several incursions into their air space by Russian military aircraft. Tensions rose as Russian intelligence forces crossed the Estonian border and captured Estonian intelligence officer Eston Kohver. In October 2014, Sweden engaged in a hunt for a foreign submarine that had entered its waters; suspicions that the submarine was Russian have caused further alarm in the Baltic states. However, the Swedish Armed Forces later admitted that the alleged sighting of a Russian sub was actually just a "workboat". The tensions in the Baltic and other areas have led neighboring Sweden and Finland, both of which have long been neutral states, to openly discuss joining NATO.