"Today I had the honour to sign the Instrument of Accession of the Republic of North Macedonia to the North Atlantic Treaty. This is the final step after 29 NATO allies ratified the accession protocol & @JensStoltenberg formally invited us to accede," Pendarovski wrote on Twitter late on Friday.
Earlier this week, Spain became the last alliance member to ratify the protocol on the membership of North Macedonia.
The nation signed an accession protocol to become a member of the alliance in February 2019. The Balkan nation becomes the North Atlantic Alliance's 30th member. The last country to join the military organisation was Montenegro back in 2017, which was preceded by Albania and Croatia in 2009.