Nato states are due to sign an agreement with Macedonia, clearing the way for the Balkan nation to become the military alliance’s 30th member.
Each Nato member will then need to ratify the accession protocol.
This comes after Greece’s MPs last month backed a deal ending a 27-year row over its northern neighbour’s name.
They approved the name Republic of North Macedonia. Greece had blocked Macedonia’s membership saying the name implied territorial ambitions.
The Greek region of Macedonia includes the country’s second city Thessaloniki. Greek lawmakers approved the deal despite widespread opposition from the public.
The prolonged dispute meant that until now Greece also frustrated Macedonia’s drive to join the European Union.
So, what about the accession protocol?
It will be signed on Wednesday at a ceremony in Brussels – the headquarters of Nato.
Nato Secretary General Jens Stoltenberg tweeted last week: “On 6 February we will write history: #NATO Allies will sign the accession protocol with the future Republic of North Macedonia together with [Macedonian] FM @Dimitrov_Nikola.”
It is not quite the final hurdle – but the long journey to becoming North Macedonia has definitely entered the home straight, the BBC’s Balkans correspondent Guy De Launey reports.
He says that Nato membership is the first significant prize for the Macedonian government.
Macedonia would have reached this point a decade ago – but Greece had blocked its membership.