NATO has formally invited the tiny Adriatic state of Montenegro to join the alliance, in its first expansion since 2009.
NATO Secretary-General Jens Stoltenberg made the announcement Wednesday during a meeting of NATO foreign ministers, calling it a "historic achievement" for the nation that was once part of Yugoslavia.
Speaking to reporters following the meeting in Brussels, U.S. Secretary of State John Kerry welcomed the move.
"Today we took another step towards the full integration of Europe and towards the common defense by inviting Montenegro into the alliance and solidifying its place in the Euro-Atlantic community of security and of values and by reaffirming also the open door policy of NATO. My government looks forward to working with Montenegro's leadership in the months ahead leading up to the Warsaw Summit in July on the accession process itself," Kerry said.
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Having instituted a number of reforms to align itself with NATO requirements, Montenegro still has tasks to fulfill - most notably, a series of accession talks with NATO officials - before it can officially join.
Montenegro's deputy prime minister Igor Luksic, speaking at the NATO meeting in Brussels Wednesday, called the invitation "a great honor" and a "historical milestone" since Montenegro became an independent country nine years ago.
‘Strong boost for security and stability’
Luksic noted that the nation of only 650,000 still has reforms to work on and pledged that his country will continue to fight corruption and organized crime while building stronger public support for NATO membership.
He said Montenegro's achievement is good news for the rest of the Balkan nations because "it means a strong boost for security and stability for the entire region."
Russia has made clear its opposition to Montenegro's joining up with Moscow's Western rivals. The coastal nation is seen in Russia as both a vacation destination and good place for foreign investment.
Meanwhile, NATO foreign ministers also reaffirmed the alliance’s commitment to extend an invitation to the Former Yugoslav Republic of Macedonia “as soon as a mutually acceptable solution to the name issue” with Greece has been reached within the framework of the United Nations.
They also reaffirmed their previous decisions for the membership of Bosnia and Herzegovina and Georgia in the NATO alliance.
NATO foreign policy chiefs also called on Russia to reverse its recognition of the South Ossetia and Abkhazia regions of Georgia as independent states and to withdraw its forces from Georgian territory.
After a short war with Georgia in early August 2008, Russia recognized Abkhazia and South Ossetia as separate republics. Since then, Georgia has maintained that Abkhazia and South Ossetia are Russian-occupied Georgian territories.