NATO chief Jens Stoltenberg has officially greeted Macedonian Prime Minister Zoran Zaev in a ceremony to mark the start of membership talks, a development that drew an angry response from Moscow.
"Detailed accession talks will now begin to help your country make its final preparation for its full membership," Stoltenberg told Zaev on the sidelines of the Western alliance's summit in Brussels on July 12.
"Once all your national procedures are completed and all NATO allies have ratified your accession, you will become the 30th member of this alliance with a seat at our table, with an equal voice in our discussions, and the equal vote in our decisions," he said.
Zaev hailed the announcement, which had been expected, as a "great, historic day" for Macedonia, a landlocked country of 2 million people in the Western Balkans region.
"This decision is a recognition of our committed engagement over more than two decades," Zaev said.
"This is recognition for the work of all Macedonian politicians, from the time of our independence up to now. It is recognition for our institutions and for all political parties. This is the recognition for all our citizens and civil society and all others who patiently waited for this day," he added.
NATO has made clear that the invitation was largely contingent upon the implementation of Macedonia's agreement with alliance member Greece to resolve a multi-decade dispute the country's official name.
Greece has long objected to Macedonia's formal designation, since one region in Greece shares the same name.
But earlier this year, the two countries settled their dispute, with the country agreeing to rename itself as North Macedonia, although some opposition remains in the country to the compromise agreement.
The prospect of Macedonia joining NATO has angered Russia, which has long opposed the eastward expansion of the alliance, fearing a military threat.
"The pulling into NATO by force of Macedonia only confirms that the policy of 'open doors' has become an aim in itself and a tool to gain control of geopolitical territory," the Russian Foreign Ministry said in a statement on July 12.
Zaev has also expressed hopes of gaining European Union membership for his country, a move that would likely anger Moscow further.
The EU had urged Macedonia to settle its dispute with Greece and also step up the pace of domestic reforms and to cut down on corruption.
"Without open perspectives for NATO and EU membership, Macedonia's future is uncertain," Macedonian Defense Minister Radmila Sekerinska said on July 10 in a nationally televised address.
"NATO membership brings stability and security," she added.