A No-Fly Zone over Ukraine and International Law

In an impassioned address to the U.S. Congress on March 16, Ukraine’s President, Volodymyr Zelensky, asked the United States for additional army support, which includes the institution of a no-fly zone.

This is a terror that Europe has not found, has not viewed for 80 a long time, and we are asking for a reply, for an answer to this terror from the total planet. Is this a lot to talk to for, to make a no-fly zone over Ukraine to preserve people? Is this much too significantly to request, humanitarian no-fly zone, a thing that Russia would not be in a position to terrorize our totally free cities? If this is too a great deal to request, we provide an substitute.

The handle follows on the heels of a single to Canadian parliamentarians in the Residence of Commons the preceding working day. In that speech, he identified as out Western States for their inaction.

Can you consider when you phone your close friends, your pleasant nations, and you check with “Please close the sky. Be sure to close the airspace. Remember to stop the bombing? How numerous extra cruise missiles have to slide on our towns right up until you make this take place?” And they, in return, categorical their deep issues about the scenario. When we talk with our associates, they say “Please keep on. Keep on a very little more time.”

Zelensky’s pleas for a no-fly zone have garnered major assistance. For occasion, the Estonian Parliament voted in favor of a resolution that urged “immediate actions to build a no-fly zone in get to protect against enormous civilian casualties in Ukraine,” an easy to understand position for a compact NATO nation bordering Russia. In the United States, 27 senior international protection specialists signed an “open letter” contacting on “the Biden administration, with each other with NATO allies, to impose a confined No-Fly Zone more than Ukraine setting up with safety for humanitarian corridors.” Signatories include things like a previous NATO Commander, former Commanding Standard of U.S. Military Europe, previous Beneath Secretaries of Defense and Condition, two previous U.S. Ambassadors to NATO, and two previous U.S. Ambassadors to Ukraine. Some associates of Congress echo their openness to these an operation (see listed here).

Nevertheless, most States stay opposed to a no-fly zone. The Biden administration has designed it crystal clear that the United States will not intervene militarily, even by suggests of a no-fly zone intended to aid evacuation of civilians and quit Russia’s targeting of Ukraine’s civilian population. White House Push Secretary Jen Psaki discussed, “A no-fly zone is escalatory and could prompt a war with Russia, a main nuclear electric power.”

Likewise, U.K. Prime Minister Boris Johnson has warned, “This is a time where miscalculation and misunderstanding is all as well achievable.” And NATO Secretary-Basic Jens Stoltenberg has been unambiguous about the NATO position.

[W]e have made it obvious that we are not likely to transfer into Ukraine, neither on the floor, or in Ukrainian airspace. And of course, the only way to implement a no-fly zone is to mail NATO planes, fighter planes into Ukrainian airspace, and then impose that no-fly zone by taking pictures down Russian planes. And our evaluation is that we comprehend the desperation. But we also think that if we did that, we’ll stop up with some thing that could close in a complete-fledged war in Europe, involving lots of additional countries, and creating a great deal additional human suffering. So that’s the cause why we make this unpleasant determination to impose weighty sanctions, offer substantial help, stepping up aid. But at the exact same time not involving NATO forces immediately in the conflict in Ukraine, neither on the ground, or in their airspace.

This submit very first describes the character of no-fly zones, drawing on 5 such zones that have been conducted. It then discusses the authorized bases for conducting these functions, together with a feasible Ukraine no-fly zone. Eventually, it highlights the knock-on lawful implications ought to a person be established in Ukrainian airspace.

No-Fly Zones

It is essential to comprehend what a no-fly zone is and what it is not. A no-fly zone is not an aerial blockade. Aerial blockades, this kind of as these carried out during the Gulf War of 1990-1991, are created to block plane entry to or exit from specified airfields or coastal places that the enemy controls. Their main objective is to protect against neutral plane from transporting substance to the enemy (See AMW Manual, sect. V listed here and in this article).

Rather, no-fly zones are a 3-dimensional piece of airspace in which designated plane are prohibited from flying (see my examination below and here). Such zones have generally been recognized without having the consent of the Point out anxious. For case in point, Functions Give Comfort (1991-1997), Northern View (1997-2003), Southern Check out (1992-2003), and NATO’s 2011 Operation Unified Protector had been mounted without the consent of Iraq or Libya, respectively. But no-fly zones might also be consensual, an case in point staying NATO’s 1993 Operation Deny Flight around Bosnia and Herzegovina. As these functions illustrate, they may be enforced by “coalitions of the willing” or a regional business like NATO.

The intent of a no-fly zone is generally humanitarian, as was the scenario with Functions Supply Ease and comfort, Northern Look at, and Southern Look at around Iraq. However, it may also be determined, at minimum in part, by armed service issues. For illustration, it is controversial that Functions Deny Flight and Unified Protector both equally sought to shift the stability of electrical power on the ground. Certainly, the previous proved unsuccessful and ultimately led in 1995 to direct NATO strikes towards Bosnian Serb forces all through NATO’s Operation Deliberate Pressure.

When a no-fly zone has been lawfully recognized (see underneath), it may well be enforced with lethal power, matter to global humanitarian legislation (IHL) guidelines in an armed conflict. Guidelines of engagement often offer for enhanced usually means of verification and escalation of drive strategies before firing on an plane in the zone. But, lethal power has been made use of, most notably in 1994 when NATO aircraft shot down 4 of six Bosnian-Serb plane that experienced dropped bombs although within Operation Deny Flight’s zone.

And no-fly zones may be established through an international armed conflict, as is remaining proposed by Ukraine. In this regard, the specialists who participated in the Guide on the Worldwide Law Relevant to Air and Missile Warfare (AMW) job (which include me) agreed that,

A Belligerent Celebration may build and implement a no-fly zone in its have or in enemy countrywide airspace. The commencement, period, locale and extent of the no-fly zones need to be correctly notified to all concerned…. [A]ircraft getting into a no-fly zone with no certain permission are liable to be attacked. (¶¶ 108-110)

The Authorized Foundation for No-Fly Zones

The doable institution of a no-fly zone around Ukraine ought to be analyzed from three views. First, any this sort of final decision necessitates thought at the strategic stage. Opponents panic escalation, while supporters spotlight the human tragedy and stress that failure to act will only embolden Russian President Putin. Both of those views are acceptable, even though I lean toward the latter.

Second, the execution of a no-fly zone is sophisticated operationally. Mark Nevitt has produced this level primarily based on his experience as a Navy aviator enforcing Operation Southern Enjoy, as have I in gentle of my encounter as the Staff Choose Advocate (SJA) for the Air Part of Operation Supply Ease and comfort and Process Force SJA for Operation Northern Watch. Nevitt and I agree that the fog of war is thick in no-fly zones, as tragically illustrated by the 1994 Blackhawk shootdown in the comparatively benign surroundings of northern Iraq.

A 3rd point of view from which to contemplate a no-fly zone is authorized. A no-fly zone is certainly lawful when licensed by the UN Stability Council less than Chapter VII of the UN Constitution. In accordance to Article 39, the Protection Council may possibly decide whether or not a scenario amounts to a “threat to the peace, breach of the peace, or act of aggression.” The moment it helps make this kind of a willpower, and if non-forcible actions to handle the condition have unsuccessful or are not likely to triumph, the Safety Council may well authorize “such action by air, sea, or land forces as might be vital to manage or restore worldwide peace and security” less than Write-up 42.

This kind of an authorization was the legal foundation for Operations Deny Flight and Unified Protector. The previous was done pursuant to Security Council Resolution 781 (1992), though Safety Council Resolution 1973 (2011) approved the no-fly zone over Libya, expressly letting for “all important measures” to enforce it, which is a phrase made use of by the UN to allow the use of power.

Since UN Stability Council authorization is the clearest basis for developing and enforcing a no-fly zone, States operate challenging to justify their operations on this ground. To illustrate, Procedure Supply Comfort and ease, the first of the Iraq no-fly zones, was justified dependent on Protection Council Resolutions 678, 687, and 688. They, respectively, approved the use of force towards Iraq in 1990, established out the phrases of the 1991 ceasefire, and condemned Iraq’s assaults on the Kurds as a threat to “international peace and protection in the area.” The a few had been examine with each other in a innovative and therefore controversial justification that held that the first use of pressure authorization remained in place, Iraq’s actions violated the ceasefire, and Iraqi assaults opened the doorway to forcible steps to shield the Kurds.

As Russia is the aggressor in Ukraine, there will be no Stability Council resolution authorizing the establishment of a no-fly zone. Having said that, at the very least in concept, it is probable that such a zone could be proven in accordance with UN Normal Assembly Resolution 377(V), the Uniting for Peace Resolution (see discussion in the Ukraine context here, listed here, and below). The resolution provides a hotly debated foundation for the use of drive. Its proponents counsel that it permits the Typical Assembly to authorize motion when the Safety Council has failed to exercising its duty for the routine maintenance of global peace and protection due to the fact of a veto by a long lasting member. While its use would conquer the Russian veto obstacle, such a resolution is unlikely.

But UN authorization, both in the type of a Safety Council resolution below Chapter VII or a Uniting for Peace Resolution, is unnecessary. Ukraine has a sovereign proper to determine which plane may possibly be current in its countrywide airspace. As a result, it may well lawfully invite the beat plane of other States into that airspace, and did so in, inter alia, the speech to Congress by President Zelensky. The invitation qualifies as “consent,” which is a floor for the preclusion of wrongfulness underneath the legislation of Condition responsibility (Articles or blog posts on Condition Duty, artwork. 20). And, of study course, Ukraine also enjoys a sovereign right to prohibit the entry into its airspace of Russian plane except if international legislation justifies their presence. As noted earlier in this symposium, Russia’s justifications for their “special military operation” are without having merit.

On the other hand, consent only decides the lawful character of the presence of enforcement (lawful) and Russian (unlawful) aircraft. Regardless of whether enforcement plane may well use power in opposition to Russian aircraft is a individual concern.

To start with, it is needed to dispense with one crimson herring. It is often asserted that the use of force by a person place (enforcement aircraft) towards yet another (Russian plane) in the territory of a third (Ukraine) is a use of drive versus that country. Having said that, there is wide consensus that a Point out may possibly consent to the use of power on its territory so extended as that use is otherwise lawful. The debate is irrelevant in this circumstance.

Equally, Ukraine’s consent obviates any have to have to glimpse to the pretty controversial doctrine of humanitarian intervention as a basis for establishing a no-fly zone. Despite the fact that a minority of States, together with the United Kingdom, are of the look at that humanitarian intervention is permissible in excessive instances (which the Ukrainian scenario qualifies as now that Russian is instantly attacking civilian population facilities), resort to the doctrine is only needed to “preclude the wrongfulness” of the sovereignty violation that the intervening States’ motion would normally represent. Ukraine’s consent by now does that function under the law of State responsibility.

This brings the investigation all around to the crux of the make any difference, the use of drive towards Russian aircraft by plane enforcing a no-fly zone. The legislation is crystal very clear. Ukraine enjoys a appropriate of self-defense in opposition to Russia’s “armed attack” beneath Write-up 51 of the UN Charter and customary intercontinental legislation. That right, in my opinion, stretches back again to the Russian 2014 functions that resulted in the profession of Crimea. And Post 51 expressly will allow for “collective” self-defense at the request, and in accordance to the parameters set forth by, a Condition that has a right of person self-protection. Ukraine has designed that ask for in the variety of a plea for a no-fly zone. It tends to make no variation whether the function of the zone would be humanitarian or to aid Ukrainian forces, for attacking Ukrainian civilians is no fewer the continuation of Russia’s first armed attack than engaging in hostilities towards the Ukrainian armed forces. Just put, Ukraine’s request for a no-fly zone permits enforcement States’ plane to 1) be existing in Ukrainian airspace and 2) use force in opposition to Russian plane violating that zone.

Legal Implications of a No-Fly Zone

A tough issue is no matter if a no-fly zone would violate the legislation of neutrality. Wolf Heintschel von Heinegg, Brian Finucane, and I have taken the posture, a single regular with the Division of Defense’s Legislation of War Guide (§ 15.2.2), that States do not violate their neutrality obligations by giving arms to the target of unequivocal aggression by yet another Point out. Russian motion qualifies in that regard, as evidenced by the UN Security Council’s vote on the subject (Russia vetoing) and the subsequent Basic Assembly resolution demanding an conclude to Russian operations. This becoming so, it would certainly not be a violation to perform a no-fly zone for humanitarian needs. But even if it were being, establishment of the zone would not as this sort of result in the Point out involved turning out to be a get together to the conflict. As a substitute, a violation of neutrality obligations is only an internationally wrongful act less than the law of Point out responsibility (see Articles on State Responsibility, art. 2).

Of program, the concern remains no matter if creating and enforcing a no-fly zone would cause an global armed conflict. Basically declaring a no fly-zone and running in Ukrainian airspace, if framed purely in humanitarian phrases, would not provide people States contributing enforcement property into the ongoing conflict. Having said that, as before long as their aircraft engaged in fight operations to enforce the zone, an worldwide armed conflict would exist among them and Russia.

This would be so, for occasion, if enforcement aircraft downed a Russian helicopter or armed forces plane or carried out “suppression of enemy air defenses” (SEAD) strikes to terminate a Russian risk to enforcement plane. Relatedly, if the no-fly zone served military uses, like carrying out “combat air patrols” intended to prevent Russian assaults on Ukrainian forces, the involvement would be at a degree wherever the States anxious would probably be considered a party to the conflict (see my discussion right here). And if Russian forces attacked the enforcement aircraft first, an worldwide armed conflict would likewise be induced.

After the international armed conflict was underway, IHL would govern the perform of hostilities by the two sides. As observed by the AMW authorities, “A Belligerent Bash is not absolved of its obligations less than the regulation of international armed conflict by developing ‘exclusion zones’ or no-fly zones” (¶105).

It need to be cautioned that, less than IHL, the armed forces assets of the imposing States would be army goals by “nature” and subject to Russian attack, even if situated outside the house Ukrainian territory. Likewise, civilian entities that have been getting utilised for armed forces needs, or even supposed for future use, like an airfield used by each armed forces and civilian aircraft, would come to be armed service targets by virtue of their “use” and “purpose” (long run use) less than IHL. No matter whether Russia would perform functions past Ukraine is debatable, but it have to be recognized that undertaking so would be lawful beneath the regulation of armed conflict.

Ultimately, it is my perspective that since the enforcement plane would be doing a humanitarian mission and lawfully be in Ukrainian airspace, any initiation of hostilities towards them by Russian aircraft or ground forces would qualify as a wrongful use of drive by Russia in violation of Posting 2(4) of the UN Constitution and customary intercontinental legislation. This is since the plane would lawfully be in Ukrainian airspace at the time. For occasion, the plane may possibly be conducting reconnaissance and surveillance in the vicinity of humanitarian corridors and be fired on with Russian floor-to-air missiles. Such a Russian use of drive might even increase to the level of an “armed attack,” thereby giving the Condition of the aircraft an impartial suitable of self-defense (different from Ukraine’s) below Write-up 51 and customary legislation.

Of training course, a practical problems would be distinguishing enforcement plane from Ukrainian overcome plane, which are lawful targets. This is so even although there are signifies to distinguish the enforcement aircraft, for example, by notifying Russian forces of their existence. The issue is that the simple fact that there is an ongoing armed conflict in Ukraine does not necessarily necessarily mean that Russia may possibly assault enforcement aircraft.


Time will tell irrespective of whether the deteriorating situation on the ground in Ukraine will cause States to rethink their place on the institution of a no-fly zone. But if they do, they would be on sound lawful footing. The concern is the will, or absence thereof, of individuals States in the encounter of Russian war crimes, not global law.


Michael N. Schmitt is the G. Norman Lieber Distinguished Scholar at the United States Armed forces Academy. He is also Professor of Public Intercontinental Law at the University of Studying, Strauss Middle Distinguished Scholar and Browsing Professor of Law at the University of Texas, and Professor Emeritus at the United States Naval War Faculty.



Image credit: U.S. Air Drive