San Remo Manual on International Law Applicable to Armed Conflicts at Sea 12 June 1994
PART I: GENERAL PROVISIONS
SECTION I: SCOPE OF APPLICATION OF THE LAW
1. The parties to an armed conflict at sea are bound by the principles and rules of international humanitarian law from the moment armed force is used.
2. In cases not covered by this document or by international agreements, civilians and combatants remain under the protection and authority of the principles of international law derived from established custom, from the principles of humanity and from the dictates of the public conscience.
SECTION II: ARMED CONFLICTS AND THE LAW OF SELF-DEFENCE
3. The exercise of the right of individual or collective self-defence recognized in Article 51 of the Charter of the United Nations is subject to the conditions and limitations laid down in the Charter, and arising from general international law, including in particular the principles of necessity and proportionality.
4. The principles of necessity and proportionality apply equally to armed conflict at sea and require that the conduct of hostilities by a State should not exceed the degree and kind of force, not otherwise prohibited by the law of armed conflict, required to repel an armed attack against it and to restore its security.
5. How far a State is justified in its military actions against the enemy will depend upon the intensity and scale of the armed attack for which the enemy is responsible and the gravity of the threat posed.
6. The rules set out in this document and any other rules of international humanitarian law shall apply equally to all parties to the conflict. The equal application of these rules to all parties to the conflict shall not be affected by the international responsibility that may have been incurred by any of them for the outbreak of the conflict.
SECTION III: ARMED CONFLICTS IN WHICH THE SECURITY COUNCIL HAS TAKEN ACTION
7. Notwithstanding any rule in this document or elsewhere on the law of neutrality, where the Security Council, acting in accordance with its powers under Chapter VII of the Charter of the United Nations, has identified one or more of the parties to an armed conflict as responsible for resorting to force in violation of international law, neutral States:
(a) are bound not to lend assistance other than humanitarian assistance to that State; and (b) may lend assistance to any State which has been the victim of a breach of the peace or an act of aggression by that State.
8. Where, in the course of an international armed conflict, the Security Council has taken preventive or enforcement action involving the application of economic measures under Chapter VII of the Charter, Member States of the United Nations may not rely upon the law of neutrality to justify conduct which would be incompatible with their obligations under the Charter or under decisions of the Security Council.
9. Subject to paragraph 7, where the Security Council has taken a decision to use force, or to authorize the use of force by a particular State or States, the rules set out in this document and any other rules of international humanitarian law applicable to armed conflicts at sea shall apply to all parties to any such conflict which may ensue.
SECTION IV: AREAS OF NAVAL WARFARE
10. Subject to other applicable rules of the law of armed conflict at sea contained in this document or elsewhere, hostile actions by naval forces may be conducted in, on or over:
(a) the territorial sea and internal waters, the land territories, the exclusive economic zone and continental shelf and, where applicable, the archipelagic waters, of belligerent States; (b) the high seas; and (c) subject to paragraphs 34 and 35, the exclusive economic zone and the continental shelf of neutral States.
11. The parties to the conflict are encouraged to agree that no hostile actions will be conducted in marine areas containing:
(a) rare or fragile ecosystems; or (b) the habitat of depleted, threatened or endangered species or other forms of marine life.
12. In carrying out operations in areas where neutral States enjoy sovereign rights, jurisdiction, or other rights under general international law, belligerents shall have due regard for the legitimate rights and duties of those neutral States.
SECTION V: DEFINITIONS
13. For the purposes of this document:
(a) international humanitarian law means international rules, established by treaties or custom, which limit the right of parties to a conflict to use the methods or means of warfare of their choice, or which protect States not party to the conflict or persons and objects that are, or may be, affected by the conflict;
(b) attack means an act of violence, whether in offence or in defence;
(c) collateral casualties or collateral damage means the loss of life of, or injury to, civilians or other protected persons, and damage to or the destruction of the natural environment or objects that are not in themselves military objectives;
(d) neutral means any State not party to the conflict;
(e) hospital ships, coastal rescue craft and other medical transports means vessels that are protected under the Second Geneva Convention of 1949 and Additional Protocol I of 1977;
(f) medical aircraft means an aircraft that is protected under the Geneva Conventions of 1949 and Additional Protocol I of 1977;
(g) warship means a ship belonging to the armed forces of a State bearing the external marks distinguishing the character and nationality of such a ship, under the command of an officer duly commissioned by the government of that State and whose name appears in the appropriate service list or its equivalent, and manned by a crew which is under regular armed forces discipline;
(h) auxiliary vessel means a vessel, other than a warship, that is owned by or under the exclusive control of the armed forces of a State and used for the time being on government non-commercial service;
(i) merchant vessel means a vessel, other than a warship, an auxiliary vessel, or a State vessel such as a customs or police vessel, that is engaged in commercial or private service;
(j) military aircraft means an aircraft operated by commissioned units of the armed forces of a State having the military marks of that State, commanded by a member of the armed forces and manned by a crew subject to regular armed forces discipline;
(k) auxiliary aircraft means an aircraft, other than a military aircraft, that is owned by or under the exclusive control of the armed forces of a State and used for the time being on government noncommercial service;
(l) civil aircraft means an aircraft other than a military, auxiliary, or State aircraft such as a customs or police aircraft, that is engaged in commercial or private service;
PART II: REGIONS OF OPERATIONS
SECTION I: INTERNAL WATERS, TERRITORIAL SEA AND ACHIPELAGIC WATERS
14. Neutral waters consist of the internal waters, territorial sea, and, where applicable, the archipelagic waters, of neutral States. Neutral airspace consists of the airspace over neutral waters and the land territory of neutral States.
15. Within and over neutral waters, including neutral waters comprising an international strait and waters in which the right of archipelagic sea lanes passage may be exercised, hostile actions by belligerent forces are forbidden. A neutral State must take such measures as are consistent with Section II of this Part, including the exercise of surveillance, as the means at its disposal allow, to prevent the violation of its neutrality by belligerent forces.
16. Hostile actions within the meaning of paragraph 15 include, inter alia:
(a) attack on or capture of persons or objects located in, on or over neutral waters or territory;
(b) use as a base of operations, including attack on or capture of persons or objects located outside neutral waters, if the attack or seizure is conducted by belligerent forces located in, on or over neutral waters;
(c) laying of mines; or
(d) visit, search, diversion or capture.
17. Belligerent forces may not use neutral waters as a sanctuary.
18. Belligerent military and auxiliary aircraft may not enter neutral airspace. Should they do so, the neutral State shall use the means at its disposal to require the aircraft to land within its territory and shall intern the aircraft and its crew for the duration of the armed conflict. Should the aircraft fail to follow the instructions to land, it may be attacked, subject to the special rules relating to medical aircraft as specified in paragraphs 181-183.
19. Subject to paragraphs 29 and 33, a neutral State may, on a non-discriminatory basis, condition, restrict or prohibit the entrance to or passage through its neutral waters by belligerent warships and auxiliary vessels.
20. Subject to the duty of impartiality, and to paragraphs 21 and 23-33, and under such regulations as it may establish, a neutral State may, without jeopardizing its neutrality, permit the following acts within its neutral waters:
(a) passage through its territorial sea, and where applicable its archipelagic waters, by warships, auxiliary vessels and prizes of belligerent States; warships, auxiliary vessels and prizes may employ pilots of the neutral State during passage;
(b) replenishment by a belligerent warship or auxiliary vessel of its food, water and fuel sufficient to reach a port in its own territory; and
(c) repairs of belligerent warships or auxiliary vessels found necessary by the neutral State to make them seaworthy; such repairs may not restore or increase their fighting strength.
21. A belligerent warship or auxiliary vessel may not extend the duration of its passage through neutral waters, or its presence in those waters for replenishment or repair, for longer than 24 hours unless unavoidable on account of damage or the stress of weather. The foregoing rule does not apply in international straits and waters in which the right of archipelagic sea lanes passage is exercised.
22. Should a belligerent State be in violation of the regime of neutral waters, as set out in this document, the neutral State is under an obligation to take the measures necessary to terminate the violation. If the neutral State fails to terminate the violation of its neutral waters by a belligerent, the opposing belligerent must so notify the neutral State and give that neutral State a reasonable time to terminate the violation by the belligerent. If the violation of the neutrality of the State by the belligerent constitutes a serious and immediate threat to the security of the opposing belligerent and the violation is not terminated, then that belligerent may, in the absence of any feasible and timely alternative, use such force as is strictly necessary to respond to the threat posed by the violation.
SECTION II: INTERNATIONAL STRAITS AND ARCHIPELAGIC SEA LANES
General rules
23. Belligerent warships and auxiliary vessels and military and auxiliary aircraft may exercise the rights of passage through, under or over neutral international straits and of archipelagic sea lanes passage provided by general international law.
24. The neutrality of a State bordering an international strait is not jeopardized by the transit passage of belligerent warships, auxiliary vessels, or military or auxiliary aircraft, nor by the innocent passage of belligerent warships or auxiliary vessels through that strait.
25. The neutrality of an archipelagic State is not jeopardized by the exercise of archipelagic sea lanes passage by belligerent warships, auxiliary vessels, or military or auxiliary aircraft.
26. Neutral warships, auxiliary vessels, and military and auxiliary aircraft may exercise the rights of passage provided by general international law through, under and over belligerent international straits and archipelagic waters. The neutral State should, as a precautionary measure, give timely notice of its exercise of the rights of passage to the belligerent State.
Transit passage and archipelagic sea lanes passage
27. The rights of transit passage and archipelagic sea lanes passage applicable to international straits and archipelagic waters in peacetime continue to apply in times of armed conflict. The laws and regulations of States bordering straits and archipelagic States relating to transit passage and archipelagic sea lanes passage adopted in accordance with general international law remain applicable.
28. Belligerent and neutral surface ships, submarines and aircraft have the rights of transit passage and archipelagic sea lanes passage through, under, and over all straits and archipelagic waters to which these rights generally apply.
29. Neutral States may not suspend, hamper, or otherwise impede the right of transit passage nor the right of archipelagic sea lanes passage.
30. A belligerent in transit passage through, under and over a neutral international strait, or in archipelagic sea lanes passage through, under and over neutral archipelagic waters, is required to proceed without delay, to refrain from the threat or use of force against the territorial integrity or political independence of the neutral littoral or archipelagic State, or in any other manner inconsistent with the purposes of the Charter of the United Nations, and otherwise to refrain from any hostile actions or other activities not incident to their transit. Belligerents passing through, under and over neutral straits or waters in which the right of archipelagic sea lanes passage applies are permitted to take defensive measures consistent with their security, including launching and recovery of aircraft, screen formation steaming, and acoustic and electronic surveillance. Belligerents in transit or archipelagic sea lanes passage may not, however, conduct offensive operations against enemy forces, nor use such neutral waters as a place of sanctuary nor as a base of operations.
Innocent passage
31. In addition to the exercise of the rights of transit and archipelagic sea lanes passage, belligerent warships and auxiliary vessels may, subject to paragraphs 19 and 21, exercise the right of innocent passage through neutral international straits and archipelagic waters in accordance with general international law.
32. Neutral vessels may likewise exercise the right of innocent passage through belligerent international straits and archipelagic waters.
33. The right of non-suspendable innocent passage ascribed to certain international straits by international law may not be suspended in time of armed conflict.
SECTION III: EXCLUSIVE ECONOMIC ZONE AND CONTINENTAL SHELF
34. 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.
35. If a belligerent considers it necessary to lay mines in the exclusive economic zone or the continental shelf of a neutral State, the belligerent shall notify that State, and shall ensure, inter alia, that the size of the minefield and the type of mines used do not endanger artificial islands, installations and structures, nor interfere with access thereto, and shall avoid so far as practicable interference with the exploration or exploitation of the zone by the neutral State. Due regard shall also be given to the protection and preservation of the marine environment.
SECTION IV: HIGH SEAS AND SEA-BED BEYOND NATIONAL JURISDICTION
36. Hostile actions on the high seas shall be conducted with due regard for the exercise by neutral States of rights of exploration and exploitation of the natural resources of the sea-bed, and ocean floor, and the subsoil thereof, beyond national jurisdiction.
37. Belligerents shall take care to avoid damage to cables and pipelines laid on the sea-bed which do not exclusively serve the belligerents.
PART III: BASIC RULES AND TARGET DISCRIMINATION
SECTION I: BASIC RULES
38. In any armed conflict the right of the parties to the conflict to choose methods or means of warfare is not unlimited.
39. Parties to the conflict shall at all times distinguish between civilians or other protected persons and combatants and between civilian or exempt objects and military objectives.
40. In so far as objects are concerned, military objectives are limited to those objects which by their nature, location, purpose or use make an effective contribution to military action and whose total or partial destruction, capture or neutralization, in the circumstances ruling at the time, offers a definite military advantage.
41. Attacks shall be limited strictly to military objectives. Merchant vessels and civil aircraft are civilian objects unless they are military objectives in accordance with the principles and rules set forth in this document.
42. In addition to any specific prohibitions binding upon the parties to a conflict, it is forbidden to employ methods or means of warfare which:
(a) are of a nature to cause superfluous injury or unnecessary suffering; or
(b) are indiscriminate, in that:
(i) they are not, or cannot be, directed against a specific military objective; or
(ii) their effects cannot be limited as required by international law as reflected in this document.
43. It is prohibited to order that there shall be no survivors, to threaten an adversary therewith or to conduct hostilities on this basis.
44. Methods and means of warfare should be employed with due regard for the natural environment taking into account the relevant rules of international law. Damage to or destruction of the natural environment not justified by military necessity and carried out wantonly is prohibited.
45. Surface ships, submarines and aircraft are bound by the same principles and rules.
SECTION II: PRECAUTIONS IN ATTACK
46. With respect to attacks, the following precautions shall be taken:
(a) those who plan, decide upon or execute an attack must take all feasible measures to gather information which will assist in determining whether or not objects which are not military objectives are present in an area of attack;
(b) in the light of the information available to them, those who plan, decide upon or execute an attack shall do everything feasible to ensure that attacks are limited to military objectives;
(c) they shall furthermore take all feasible precautions in the choice of methods and means in order to avoid or minimize collateral casualties or damage; and
(d) an attack shall not be launched if it may be expected to cause collateral casualties or damage which world be excessive in relation to the concrete and direct military advantage anticipated from the attack as a whole; an attack shall be cancelled or suspended as soon as it becomes apparent that the collateral casualties or damage would be excessive.
Section VI of this Part provides additional precautions regarding civil aircraft.
SECTION III: ENEMY VESSELS AND AIRCRAFT EXEMPT FROM ATTACK
Classes of vessels exempt from attack
47. The following classes of enemy vessels are exempt from attack:
(a) hospital ships;
(b) small craft used for coastal rescue operations and other medical transports;
(c) vessels granted safe conduct by agreement between the belligerent parties including:
(i) cartel vessels, e.g., vessels designated for and engaged in the transport of prisoners of war;
(ii) vessels engaged in humanitarian missions, including vessels carrying supplies indispensable to the survival of the civilian population, and vessels engaged in relief actions and rescue operations;
(d) vessels engaged in transporting cultural property under special protection;
(e) passenger vessels when engaged only in carrying civilian passengers;
(f) vessels charged with religious, non-military scientifc or philanthropic missions, vessels collecting scientific data of likely military applications are not protected;
(g) small coastal fishing vessels and small boats engaged in local coastal trade, but they are subject to the regulations of a belligerent naval commander operating in the area and to inspection;
(h) vessels designated or adapted exclusively for responding to pollution incidents in the marine environment;
(i) vessels which have surrendered;
(j) life rafts and life boats.
Conditions of exemption
48. Vessels listed in paragraph 47 are exempt from attack only if they:
(a) are innocently employed in their normal role;
(b) submit to identification and inspection when required; and
(c) do not intentionally hamper the movement of combatants and obey orders to stop or move out of the way when required.
Loss of exemption
Hospital ships
49. The exemption from attack of a hospital ship may cease only by reason of a breach of a condition of exemption in paragraph 48 and, in such a case, only after due warning has been given naming in all appropriate cases a reasonable time limit to discharge itself of the cause endangering its exemption, and after such warning has remained unheeded.
50. If after due warning a hospital ship persists in breaking a condition of its exemption, it renders itself liable to capture or other necessary measures to enforce compliance.
51. A hospital ship may only be attacked as a last resort if:
(a) diversion or capture is not feasible; (b) no other method is available for exercising military control;
(c) the circumstances of non-compliance are sufficiently grave that the hospital ship has become, or may be reasonably assumed to be, a military objective; and
(d) the collateral casualties or damage will not be disproportionate to the military advantage gained or expected.
All other categories of vessels exempt from attack
52. If any other class of vessel exempt from attack breaches any of the conditions of its exemption in paragraph 48, it may be attacked only if:
(a) diversion or capture is not feasible;
(b) no other method is available for exercising military control;
(c) the circumstances of non-compliance are sufficiently grave that the vessel has become, or may be reasonably assumed to be, a military objective; and
(d) the collateral casualties or damage will not be disproportionate to the military advantage gained or expected.
Classes of aircraft exempt from attack
53. The following classes of enemy aircraft are exempt from attack:
(a) medical aircraft;
(b) aircraft granted safe conduct by agreement between the parties to the conflicts; and
(c) civil airliners.
Conditions of exemption for medical aircraft
54. Medical aircraft are exempt from attack only if they:
(a) have been recognized as such;
(b) are acting in compliance with an agreement as specified in paragraph 177;
(c) fly in areas under the control of own or friendly forces; or
(d) fly outside the area of armed conflict. In other instances, medical aircraft operate at their own risk.
Conditions of exemption for aircraft granted safe conduct
55. Aircraft granted safe conduct are exempt from attack only if they:
(a) are innocently employed in their agreed role;
(b) do not intentionally hamper the movements of combatants; and
(c) comply with the details of the agreement, including availability for inspection.
Conditions of exemption for civil airliners
56. Civil airliners are exempt from attack only if they:
(a) are innocently employed in their normal role; and
(b) do not intentionally hamper the movements of combatants. Loss of exemption
57. If aircraft exempt from attack breach any of the applicable conditions of their exemption as set forth in paragraphs 54-56, they may be attacked only if:
(a) diversion for landing, visit and search, and possible capture, is not feasible;
(b) no other method is available for exercising military control;
(c) the circumstances of non-compliance are sufficiently grave that the aircraft has become, or may be reasonably assumed to be, a military objective; and
(d) the collateral casualties or damage will not be disproportionate to the military advantage gained or anticipated.
58. In case of doubt whether a vessel or aircraft exempt from attack is being used to make an effective contribution to military action, it shall be presumed not to be so used.
SECTION IV: OTHER ENEMY VESSELS AND AIRCRAFT
Enemy merchant vessels
59. Enemy merchant vessels may only be attacked if they meet the definition of a military objective in paragraph 40.
60. The following activities may render enemy merchant vessels military objectives:
(a) engaging in belligerent acts on behalf of the enemy, e.g., laying mines, minesweeping, cutting undersea cables and pipelines, engaging in visit and search of neutral merchant vessels or attacking other merchant vessels;
(b) acting as an auxiliary to an enemy s armed forces, e.g., carrying troops or replenishing warships;
(c) being incorporated into or assisting the enemy s intelligence gathering system, e.g., engaging in reconnaissance, early warning, surveillance, or command, control and communications missions;
(d) sailing under convoy of enemy warships or military aircraft;
(e) refusing an order to stop or actively resisting visit, search or capture;
(f) being armed to an extent that they could inflict damage to a warship; this excludes light individual weapons for the defence of personnel, e.g., against pirates, and purely deflective systems such as chaff ; or
(g) otherwise making an effective contribution to military action, e.g., carrying military materials.
61. Any attacks on these vessels is subject to the basic rules set out in paragraphs 38-46.
Enemy civil aircraft
62. Enemy civil aircraft may only be attacked if they meet the definition of a military objective in paragraph 40.
63. The following activities may render enemy civil aircraft military objectives:
(a) engaging in acts of war on behalf of the enemy, e.g., laying mines, minesweeping, laying or monitoring acoustic sensors, engaging in electronic warfare, intercepting or attacking other civil aircraft, or providing targeting information to enemy forces;
(b) acting as an auxiliary aircraft to an enemy's armed forces, e.g., transporting troops or military cargo, or refuelling military aircraft;
(c) being incorporated into or assisting the enemy's intelligence-gathering system, e.g., engaging in
