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.
1997 Madrid summit
The topic of enlargement was the main focus of the summit. The result of the summit was that Hungary, Poland, and the Czech Republic were invited to join NATO. Fellow Visegrád Group member Slovakia was excluded from this invitation. Slovakia had held a referendum on NATO membership in May 1997, but turnout in the referendum failed to achieve the required 50% of eligible voters and government sabotage was blamed, which in turn was viewed as one of a string of undemocratic measures taken by Prime Minister Vladimír Mečiar. A majority of NATO members reportedly supported France's proposal to also immediately invite Romania and Slovenia as members, but this was strongly opposed by U.S. President Bill Clinton, and even a "iron-clad guarantee" that they could be invited in two years time was watered-down in favor of an "open door" policy for new potential members. A main concern for the United States was the cost of potentially raising the military standards of the new Eastern European members. Estimates put this cost at as much as $10 billion USD, which participants worried could lead to the treaty recognizing the new members being rejected by the Republican-held U.S. Senate. Additionally, a "Charter on a Distinctive Partnership" was signed between NATO and Ukraine, creating the NATO-Ukraine Commission and establishing relations between the two, and a declaration supporting peace efforts in Bosnia-Herzegovina was read and signed by participants.