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How can Ukraine join NATO?

By Matthew Parish

The North Atlantic Treaty Organisation is a multilateral defence cooperation agreement signed in 1949 the purpose of which is and was always to defend the western liberal democracies and their allies against the threats posed by the Soviet Union. The Soviet Union was a transformation of the Russian Empire into a new ideological mould but with the furthest boundaries west that the Russian Empire had ever absorbed: as far as taking half of Germany into its dominion. Now the battle conflict between the West and the Russian Empire has emerged again, we are faced with the same dilemma of Russian imperialism and how to coordinate the West’s military efforts to thwart it.

Because Russia remains the largest country in the world, and although the Soviet Union may have gone a number of the constituent territories that emerge in its wake remain substantially under Russian influence. In her two invasions of Ukraine over the last decade Russia has shown her imperial ambitions once again, this time extending east, and therefore precisely the same threat has emerged as that NATO was designed to counteract. NATO’s purposes are therefore reinvigorated with the war in Ukraine, and the organisation is ever more relevant as a massive land war is carried out with Russia in Ukraine in which all manner of western troops are increasingly dragged in, even if not (yet) officially under the NATO umbrella, and an existential struggle for the future of Ukraine is being acted out.

Therefore two questions emerge, if we are to maintain our common western foreign policy goals of keeping Ukraine independent and free from the Russian Federation. One is the desirability of Ukraine joining NATO; the second is whether it is diplomatically, legally and politically possible. The answer to both questions is yes.

NATO was effective during the first Cold War as an absolute deterrent against Soviet (now Russian) aggression, and that is precisely what is necessary now to prevent further Russian aggression against Ukrainian territory. It is inconceivable to imagine that Russia would desist from her current conflict in Ukraine unless and until NATO engages. NATO troops seem likely to enter in some sort of formal capacity Ukrainian territory in the course of 2024, although nobody knows quite if or when given all the electoral uncertainties in the the West. However that is not of course the same as joining NATO, because NATO troops can enter under a NATO banner (or not - but with NATO central command coordination) without Ukraine first joining NATO. Article 4 of the NATO Treaty provides for that. The value of Ukraine’s actually joining NATO would be Article 5 of the North Atlantic Treaty, which entails the collective obligation of self-defence where a NATO member state’s armed forces are attacked on its territory. Obviously NATO membership would serve as a massive legal deterrent to Russian aggression.

Is it possible as a theoretical matter? It has been said that having no territorial disputes is a prerequisite to joining NATO, although this is not in fact stated anywhere in the North Atlantic Treaty and it would appear to be mere diplomats’ surmise rather than a statement of legal or diplomatic principle. West Germany joined NATO in 1955, notwithstanding that it had territorial disputes with East Germany until 1970. Moreover an exclave of West Germany, West Berlin, was surrounded by East Germany in the most hostile of conditions that had led to the Berlin Blockade between 1948 and 1949 and yet the NATO member states still decided to permit West Germany (as it then was) to join. A better principle might be that it is exceptional to allow a country with territorial disputes to join; but in the case of Ukraine we have precisely such an exceptional case. The Russian Federation agreed to respect the territorial integrity of Ukraine in exchange for Ukraine’s giving up of nuclear weapons in the Lisbon Protocol of 1993, and this agreement was guaranteed by two of NATO’s principal member states, the United States and the United Kingdom. Therefore in international law there is no territorial dispute; there has just been an invasion, that Russia has not even attempted to justify whether legally or on any other basis. So this adage is empty.

What would be unusual about Ukrainian accession to NATO is that only part of Ukraine would be acceding to NATO; that is to say, what we call “free Ukraine”. The occupied parts of Ukraine would be reserved in a a protocol for later accession to Ukraine once they had been liberated. However theoretical in the immediate future such liberation might appear, they could also join. No express provision for such possibilities is made in the North Atlantic Treaty as it currently stands; but given that the consent of all the NATO member states would be required for Ukraine to accede, they could likewise unanimously assent to a Ukraine protocol which gives effect to these intricacies.

This leaves the question of whether NATO’s outlying member states, particularly Hungary, Slovakia and Turkey, would consent. In Hungary there is evidence that Prime Minister Viktor Orbán’s ostensible pro-Russian views are moderating, as a compromise was reached providing Hungary with EU financial support in exchange for assent to a recent EU package of aid to Ukraine. In Slovakia there are imminent important Presidential elections pitting a more pro-Russian candidate against a more pro-Ukrainian one; but with small countries theoretical veto powers are not as compelling as they might appear because there are so many things the larger member states within any pact can take away from the smaller powers and therefore Hungary and Slovakia could expect to be pulled around, particularly if the United States threatened to withdraw its own NATO protection umbrella from these states. As to Turkey, her own mediation efforts, principally designed to keep the free Ukrainian port of Odessa open to permit Ukrainian grain to flow to the Middle East where it is relied upon to keep food in ample supply and food prices down, has been rebuffed. Therefore Turkish President Erdoğan might use the opening of NATO accession negotiations with Ukraine as a lever to discipline Russia whose resilience to international political opinion is now tiring Ankara.

There is a process anticipated under the North Atlantic Treaty for incorporation of an accession state’s troops into NATO’s command and control structures but in the context of NATO member states training and arming the Ukrainian Armed Forces this has already been taking place. In short, there is a compelling case that even at war, and indeed precisely because this is the best way of stopping the war, Ukrainian membership of NATO (limited to free Ukraine, with the rest being deferred to some future political resolution of the conflict between the two gigantic neighbours) might come a long time before EU membership for Ukraine. But the first step is for NATO troops officially to enter Ukraine upon Ukraine’s invitation, and then the legal and diplomatic machinations behind the scenes to transform Ukraine into a NATO member state can begin.


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