 The last provision of chapter 7 of the United Nations Charter is article 51, which reads as follows. I quote, Nothing in the present Charter shall impair the inherent right of individual or collective self-defense if an armed attack occurs against a member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security. Measures taken by members in the exercise of this right of self-defense shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary in order to maintain or restore international peace and security, end of quote. In the Nicaragua case, the International Court of Justice considered that the right of self-defense was an exception to the prohibition to use force. This is paragraph 193 and 210 of the judgment of 86. In the oil platforms case, the Court called it a qualification to such prohibition, but this does not mean anything different. The important thing is to see that if self-defense is an exception to article 2, paragraph 4 of the Charter, then the two rules, the obligation not to use force and the right of self-defense, they form together a system of connected vessels. The larger the scope of the exception, the narrower the prohibition and vice-versa. So the scope of the prohibition to use force cannot be defined separately from the right of self-defense. You may also remember that under article 21 of Arciois, the Articles on State Responsibility, self-defense is conceptually constructed as a circumstance precluding wrongfulness. As such, self-defense is a use of force which is directed against the territorial integrity or political independence of another state, but the wrongfulness of such act is precluded because it is taken in self-defense. You may also have noticed that article 51 of the UN Charter characterizes the right of self-defense as being an inherent right of states, and by this the Charter underscores the elementary fundamental character of such right, the fact that it is intrinsically linked to sovereignty and also it underscores its customary nature. However self-defense is also regulated under article 51 of the Charter, so the difficulty that arises when addressing the right of self-defense is that one must combine the text of the Charter with the relevant rules of country international law that govern self-defense. Article 51 refers to the right of individual or collective self-defense, but let me first address individual self-defense and turn to collective self-defense later. Article 51 begins by referring to a specific situation which triggers the inherent right of self-defense, if an armed attack occurs against a member of the United Nations. And let us stop here for a moment and address first the notion of armed attack. That is an armed attack that opens the right to use force in self-defense. The French version of the Charter, which is equally authentic, the French version does not refer to an attack armée or armed attack, but to une agression armée. Aggression seems to refer to a user for which is more serious than an armed attack, therefore seemingly putting the threshold slightly higher and limiting the possibility to use force in self-defense. And there has been endless debates about that discrepancy and the francophone and anglophone schools of international law are respectively marked by that difference when it comes to discussing self-defense. However, one should go beyond it and take stock of the fact that both French and English require that the armed attack reaches a certain threshold of gravity in order to open the right to use force in self-defense. In other words, border skirmishes, for instance, do not legally trigger the right of self-defense. And the International Court of Justice has stressed that it was, I quote, necessary to distinguish the most grave forms of the use of force, those constituting an armed attack, from other less grave forms. And that was in the Nicaragua Judgment paragraph 191. Furthermore, the court has requested in the oil platform case that the attack, that the armed attack be not at random, that it be specifically directed at the victim state with a specific intent to harm it. Because an act of aggression is necessarily an armed attack within the meaning of Article 51, guidance can also be found in Resolution 3314 on the definition of aggression. That resolution was adopted by the General Assembly on 14 December 1974 for the purpose of helping the Security Council to qualify situations as aggressions. Under Resolution 3314 that you can find in the reading material, the first use of armed force by a state in contravention of the Charter is set to constitute prima facie evidence of an act of aggression. The Security Council may, however, disqualify such prima facie qualification in light of all the circumstances. Furthermore, Article 3 of Resolution 3314 refers to several acts that are considered as qualifying as acts of aggression. And those acts include the invasion of a territory, its annexation, the bombardment of the territory of another state, the blockade of its ports, the attack on the armed forces of another state, etc. The list is not exhaustive and the Security Council may consider other acts as acts of aggression.