This subsection is without prejudice to the rights of proclaiming “Air Defence Identification Zones” (ADIZ) or “Flight Information Regions” (FIR). These rights are enjoyed by every State, in times both of peace and armed conflict. ADIZs are zones established in international airspace adjacent to national airspace by which States establish reasonable conditions of entry into their territory. FIR is an aviation term used to describe airspace with specific dimensions, in which a flight information service and an alerting service are provided. Oceanic airspace is divided into Oceanic Information Regions and delegated to controlling authorities bordering that region. The division of authorities is done by international agreement through ICAO.

1. Rule 105 (a) emphasizes that, by establishing “exclusion zones” or no-fly zones, Belligerent Parties are not absolved from their obligations under the law of international armed conflict,^[602] nor do they acquire additional rights. Laws concerning neutrality (see section X) and targeting (see Section D), in particular, still apply within a zone.
2. Aircraft not qualifying as military objectives may not be attacked for the mere reason of being encountered within an “exclusion zone” or a no-fly zone. While unauthorized presence in a zone may be considered an indicator of hostile intent, the principles of target discrimination as well as the rules on feasible precautions in attack still apply (see Sections D; E and G).^[603]
3. “Exclusion zones” or no-fly zones may not be abused for preventing enemy exports on board neutral aircraft (or vessels). The only lawful method for achieving that goal is blockade (for aerial blockade, see Section V).

602. Para. 13.78 of the UK Manual: “Should a belligerent, as an exceptional measure, establish such a zone: (a) the same body of law applies both inside and outside the zone.”
     
     Para. 7.9 of NWP, in the second Para. thereof: “the establishment of such a zone does not relieve the proclaiming belligerent of the obligation under the law of armed conflict to refrain from attacking vessels and aircraft that do not constitute lawful targets. In short, an otherwise protected platform does not lose that protection by crossing an imagi-nary line drawn in the ocean by a belligerent.”
603. See also Para. 12.58 of the UK Manual: “The right to fire upon any aircraft disregarding a general prohibition of entry into such a zone must be based on military necessity. That requires an assessment as to whether in all circum-stances the aircraft is a military objective and whether an attack upon it can be carried out without disproportionate loss of civilian life or civilian property.”

1. Rule 105 (b) clearly prohibits any form of unrestricted air and missile attacks, i.e. attacks on sight against all objects and persons encountered within the zone without prior target identification or precautionary measures (see Canadian Joint Doctrine Manual^[604] and Para. 7.9 of NWP^[605] ).^[606] Sometimes, the term “free-fire zone” is used in this context. Since, however, that is not a legal term of art, the Group of Experts preferred the use of the more established term “unrestricted … attacks”.
2. Aircraft may not be attacked based on mere presence in an “exclusion zone” or in a no-fly zone. Air-craft can only be attacked if they constitute military objectives in accordance with all the criteria discussed in Rule 1 (y) and Section E before being made the object of attack.
3. However, the prohibition of unrestricted warfare is without prejudice to the possibility of a specific area of land being a military objective on the basis of the location criterion (see Rule 1 (y) and Rule 22 (b)).^[607]

604. Para. 852 of the Canadian Joint Doctrine Manual: “(1) Parties to naval conflicts have on a number of occa-sions established different kinds of zones in and over water areas that deny or restrict access to vessels and aircraft of states that are not parties to the conflict. Vessels or aircraft entering such zones risk being attacked. These zones have been given a variety of names including exclusion zones, military areas, barred areas, war zones and operational zones. (2) A belligerent is not absolved of its duties under International Law by establishing zones that might ad-versely affect the legitimate uses of defined areas of the sea. In particular, such zones are not “free fire zones.”
605. Para. 7.9 of NWP, third paragraph thereof: “Because exclusion and war zones are not simply free fire zones for the warships of the belligerents, the establishment of such a zone carries with it certain obligations for belligerents with respect to neutral vessels entering the zones.”
606. See also Para. 8.18 of the Australian Book of Reference 5179 Manual of International Law.
607. See, e.g., the statement made by the UK on ratification of AP/I, pertaining to Art. 52 of AP/I: “It is the under-standing of the UK that a specific area of land may be a military objective if, because of its location or other reasons specified in this Article, its total or partial destruction, capture or neutralisation in the circumstances ruling at the time offers definite military advantage.”

1. As indicated in paragraph 11 of the chapeau to this Section, “exclusion zones” and no-fly zones must be distinguished from other well-established belligerent rights, such as the right of belligerent control within the immediate area of operations.^[608]
2. The concept “immediate vicinity of hostilities” includes the contact zone on land and the counterpart area at sea or in the air in which hostilities are taking place or in which belligerent forces are actually operating in support of the hostilities.
3. In order to prevent “civil aviation in the immediate vicinity of hostilities” from jeopardizing the military operations through (i) presence; or (ii) communication with anyone outside that area, a Belligerent Party may prohibit civil aviation from entering that area, or may establish special restrictions upon flights or activities (e.g., by controlling or blocking their communication).^[609]
4. Art. 30 of the HRAW provides: “In case a belligerent commanding officer considers that the presence of aircraft is likely to prejudice the success of the operations in which he is engaged at the moment, he may prohibit the passing of neutral aircraft in the immediate vicinity of his forces or may oblige them to follow a particular route. A neutral aircraft which does not conform to such directions, of which it has had a notice issued by the belligerent commanding officer, may be fired upon.”

608. Para. 12.58 of the UK Manual: “Parties to a conflict may establish zones of immediate operations or exclusion zones within which they intend to pursue or are actively pursuing hostilities.”
     Para. 7.8 of NWP, see fn. 601.
     Para. 703 of the Canadian Joint Doctrine Manual: “2. Operational Zones. Parties to a conflict may, by appropriate notice, establish areas of immediate air operations where they pursue combat activities. Such zones may exist over the territories and territorial waters of all states involved in the hostilities. All aircraft entering such zones, including the aircraft of neutral states, risk damage from the hostilities.”
609. Para. 108 of SRM/ACS, see fn. 600.

1. Rule 106 (b) relates to “force protection”, which is a generally recognized belligerent right. Such measures may include the establishment and enforcement of “warning zones” around naval units (“defence bubbles”) or around military units stationed on the ground, and other measures the responsible commander considers necessary in view of a given threat.
2. Such “warning zones” merely serve to keep aviation or navigation at a distance from the force subject to protection, and to indicate that — should they enter the zone — they are at increased risk of defensive action. The establishment of a “warning zone” may never result in attacks without prior warning. However, aircraft approaching a “warning zone” may become liable to attack if, after prior warning, they continue on their course and military necessity warrants attack.

1. This Rule specifies the criteria that are constitutive for the legality of an “exclusion zone”. The preconditions spelled out in Rule 107 (a) − (e) must be fulfilled cumulatively.
2. The expression “international airspace”, as used in Rule 107, has been understood by the Group of Experts not to be applicable to any parts of the airspace above Antarctica, and this notwithstanding paragraph 8 of the Commentary on Rule 1 (a). Although some parts of Antarctica are considered “territory not subject to the sovereignty of any State”, there is no right for a Belligerent Party to establish an exclusion zone in the airspace above Antarctica.

1. Rule 107 (a) re-emphasizes the general Rule set out in Rule 105 (a) that a Belligerent Party, by establishing an “exclusion zone”, neither acquires additional rights nor becomes absolved from its obligations under the law of international armed conflict. Laws concerning neutrality and targeting, in particular, still apply within an “exclusion zone” (see the Commentary on Rule 105).
2. A Belligerent Party may, as a matter of policy, decide to limit the hostilities to the area covered by the “exclusion zone”.

1. There are no specific limits on the extent, location and duration of an “exclusion zone” or the measures imposed within it on international aviation. All this will depend upon the circumstances of each case. There must, however, be a reasonable and proportionate nexus between the zone and considerations of military necessity. The weight of the latter must be established in light of the specific purpose pursued with the establishment of the “exclusion zone”.
2. Moreover, the nature of the respective area in which the zone is established ought to be taken into con-sideration. For instance, the location of major civil aviation routes within the zone and subsequent impact on neutral trade may be a factor in assessing what is “reasonably required by military necessity”.

1. Since an “exclusion zone” is established and enforced in international airspace, it necessarily impacts on international civil aviation (and navigation). A Belligerent Party cannot expect international civil aviation (and navigation) to observe the restrictions imposed if neutral aircraft (and vessels) are unaware of the zone, its location, extent and duration.
2. Therefore, based on Rule 107 (c), the Belligerent Party establishing an “exclusion zone” is obliged to publicize these details as well as the restrictive measures it purports to apply within the “exclusion zone”. The term “notify” is to be understood in a non-technical manner. It is not necessary to communicate the information via diplomatic channels. In most cases it will be appropriate to make use of a NOTAM.

1. Neutral territory, including neutral airspace, is inviolable under the law of international armed conflict (see Rule 166). Moreover, the existence of an international armed conflict does not deprive a Neutral of its right to use its national airspace for all lawful purposes, such as egress from and entry into international airspace, as well as military exercises and operations. Based on Rule 107 (d), Belligerent Parties are under an affirmative obligation to respect these neutral rights.
2. One ought to distinguish between (i) what is impermissible (i.e. the establishment of an “exclusion zone” encompassing neutral airspace within the zone); and (ii) what is permissible (i.e. the establishment of an “exclusion zone” in areas of the high seas, including for this purpose the EEZ, provided that adequate access / exit routes are established). While an “exclusion zone” encompassing neutral airspace within the zone will always be illegal, the mere fact that access to neutral airspace on certain routes is no longer possible, or has become restricted, is not sufficient to render an “exclusion zone” illegal. However, a partial barring of access to neutral airspace may be a violation of the Neutral’s rights if other access routes of similar safety and convenience are unavailable.

1. The obligation of Belligerent Parties to pay due regard to the rights of Neutrals is not limited to areas in which Neutrals enjoy territorial sovereignty. According to Rule 107 (e), which is derived from Art. 58^[610] and Art. 87 of UNCLOS,^[611] Belligerent Parties are obliged to pay due regard to installations and other structures Neutrals have established in accordance with the respective provisions of the law of the sea.^[612] As long as they are paying such due regard to artificial islands, installations, structures and safety zones, Belligerent Parties are free to conduct military activities within the EEZ of Neutrals (see also paragraph 8 of the Commentary on Rule 1 (b)) and the third paragraph of the Commentary on Rule 166).
2. The “due regard” principle is a concept of the law of the sea and therefore established in peacetime international law. In the relations between Belligerent Parties and Neutrals, the law of the sea — to the extent it does not conflict with the law of neutrality — continues to apply. It needs to be stressed that the “due regard” principle imposes no absolute and affirmative obligation. According to that principle, Belligerent Parties are called upon to balance the military advantages anticipated with the negative impact on the Neutral’s rights in the respective airspace and sea areas.
3. Members of the Group of Experts disagreed over whether Rule 107 (e) reflects customary international law. Some members of the Group of Experts felt that there was no established State practice with regard to this principle.

610. Art. 58 UNCLOS (“Rights and duties of other states in the exclusive economic zone”): “(1) In the exclusive economic zone, all States, whether coastal or land-locked, enjoy, subject to the relevant provisions of this Convention, the freedoms referred to in Article 87 of navigation and overflight and of the laying of submarine cables and pipelines, and other internationally lawful uses of the sea related to these freedoms, such as those associated with the operation of ships, aircraft and submarine cables and pipelines, and compatible with the other provisions of this Convention. (2) Articles 88 to 115 and other pertinent rules of international law apply to the exclusive economic zone insofar as they are not incompatible with this Part. (3) In exercising their rights and performing their duties under this Convention in the exclusive economic zone, States shall have due regard to the rights and duties of the coastal State and shall comply with the laws and regulations adopted by the coastal State in accordance with the provisions of this Convention and other rules of international law insofar as they are not incompatible with this Part.”
611. Art. 87 UNCLOS (“Freedom of the high seas”): “(1) The high seas are open to all States, whether coastal or land-locked. Freedom of the high seas is exercised under the conditions laid down by this Convention and by other rules of international law. It comprises, inter alia, both for coastal and land-locked States: (a) freedom of navigation; (b) freedom of overflight; (c) freedom to lay submarine cables and pipelines, subject to Part VI; (d) freedom to construct artificial islands and other installations permitted under international law, subject to Part VI; (e) freedom of fishing, subject to the conditions laid down in section 2; (f) freedom of scientific research, subject to Parts VI and XIII. (2) These freedoms shall be exercised by all States with due regard for the interests of other States in their exercise of the freedom of the high seas, and also with due regard for the rights under this Convention with respect to activities in the Area.”
612. Para. 34 of SRM/ACS: “If hostile actions are conducted within the exclusive economic zone or on the continental shelf of a neutral state, belligerent states shall, in addition to observing the other applicable rules of the law of armed conflict at sea, have due regard for the rights and duties of the coastal state, inter alia, for the exploration and exploitation of the economic resources of the exclusive economic zone and the continental shelf and the protection and preservation of the marine environment. They shall, in particular, have due regard for artificial islands, installations, structures, and safety zones established by neutral states in the exclusive economic zone and on the continental shelf.” Similar language is also used in Para. 13.21 of the UK Manual.

The object and purpose of this Rule is to emphasize this belligerent right and to distinguish no-fly zones from “exclusion zones”. For the purposes of this Manual, no-fly zones cannot be established in international airspace.

A Belligerent Party establishing and enforcing a no-fly zone is under an obligation to publicize the details laid down in Rule 109 to “all concerned”, i.e. to civil aviation — own, enemy or neutral — if the zone will have an impact on such aviation. There is no obligation to inform enemy military aircraft (which are military objectives by nature). As to the means of communicating the details (e.g., by NOTAM), see paragraph 2 of the Commentary on Rule 107 (c).

1. Sections D and G deal, respectively, with attacks and precautions in attack.
2. Rule 110 reflects that unauthorized presence in a no-fly zone may be considered an indicator of hostile intent, but in no way implies that mere presence within the zone is sufficient to warrant attack. In other words, such presence by itself does not trigger the application of the criterion of “location” to render it a military objective under Rule 22 (b).
3. As emphasized in the UK Manual, “attacks on ostensibly civil aircraft ought only to be carried out as a last resort when there is reason to believe that it is itself deployed on an attack”.^[613]
4. Rule 110 does not authorize automatic engagement or a “free-fire zone”. As in “exclusion zones”, the principles of target discrimination (Sections D and E) and the Rules of Section G still apply.

613. Para. 12.58.2. of the UK Manual: “The presumption, in Additional Protocol I, of civilian status in cases of doubt does not, strictly speaking, apply in air-to-air combat [see Art. 49 (4) of AP/I] Nevertheless, attacks on ostensibly civil aircraft should only be carried out as a last resort when there is reason to believe that it is itself deployed on an attack. An example might be when, during an armed conflict, an exclusion zone has been established around the United Kingdom and an apparently civilian airliner enters the zone on a course set for a major city, all required notification and other procedures to establish the zone have been meticulously completed, and all attempts to communicate with the aircraft, including buzzing, have failed or been ignored.”