The Charter of the United Nations: Chapter VII (use of force)
CHAPTER VII ACTION IN CASE OF THREAT TO THE PEACE, BREACH OF THE PEACE AND ACT OF AGGRESSION
Article 39 - threat to peace
The Security Council determines the existence of a threat to the peace, a breach of the peace or an act of aggression and makes recommendations or decides what measures will be taken in accordance with Articles 41 and 42 to maintain or restore international peace and security.
Article 40 – Provisional measures
In order to prevent the situation from deteriorating, the Security Council, before making the recommendations or deciding on the measures to be taken in accordance with Article 39, may invite the parties concerned to comply with such provisional measures as it deems necessary or desirable. These provisional measures in no way prejudice the rights, claims or position of the interested parties. In the event of non-execution of these provisional measures, the Security Council shall take due account of this failure.
Article 41 - Embargo measures
The Security Council may decide what measures not involving the use of armed force must be taken to give effect to its decisions, and may call on Members of the United Nations to apply such measures. These may include the complete or partial interruption of economic relations and of rail, sea, air, postal, telegraphic, radio and other means of communication, as well as the severance of diplomatic relations.
Article 42 - Use of force
If the Security Council considers that the measures provided for in Article 41 would be inadequate or that they have proved to be so, it may take, by means of air, naval or land forces, any action it deems necessary to maintain or to the restoration of international peace and security. This action may include demonstrations, blockade measures and other operations carried out by the air, naval or land forces of Members of the United Nations.
Article 43 - Member States contribution
1. All Members of the United Nations, in order to contribute to the maintenance of international peace and security, undertake to place at the disposal of the Security Council, at its invitation and in accordance with a special agreement or special agreements , armed forces, assistance and facilities, including the right of passage, necessary for the maintenance of international peace and security.
2. The agreement or agreements referred to above shall determine the strength and nature of these forces, their degree of readiness and general location, and the nature of the facilities and assistance to be provided.
3. The agreement or agreements will be negotiated as soon as possible, on the initiative of the Security Council. They will be concluded between the Security Council and Members of the Organization, or between the Security Council and groups of Members of the Organization, and must be ratified by the signatory States according to their respective constitutional rules.
Article 44 - Participation in decisions
When the Security Council has decided to resort to force, it shall, before inviting a Member not represented on the Council to contribute armed forces in execution of the obligations contracted under Article 43, invite that Member, if that so desire, to participate in the decisions of the Security Council concerning the employment of contingents of the armed forces of that Member.
Article 45 - On-call quotas
In order to enable the Organization to take urgent military measures, Members of the United Nations shall maintain national contingents of air forces immediately available for the combined execution of international coercive action. Within the limits provided for in the special agreement or agreements referred to in Article 43, the Security Council, with the assistance of the Military Staff Committee, determines the size and the degree of readiness of these contingents and draws up plans for their combined action.
Article 46 - Planning
Plans for the use of armed force are established by the Security Council with the assistance of the Military Staff Committee.
Article 47 - Staff Committee
1. A Military Staff Committee is hereby established to advise and assist the Security Council in all matters relating to the military means necessary for the Council to maintain international peace and security, the employment and the command of the forces placed at its disposal, the regulation of armaments and eventual disarmament.
2. The Military Staff Committee shall be composed of the Chiefs of Staff of the permanent members of the Security Council or their representatives. It invites any Member of the United Nations which is not permanently represented on the Committee to join it, when the participation of this Member in its work is necessary for the proper performance of its task.
3. The Military Staff Committee is responsible, under the authority of the Security Council, for the strategic direction of all armed forces placed at the disposal of the Council. Questions relating to the command of these forces will be settled later.
4. Regional sub-committees of the Military Staff Committee may be established by it with the authorization of the Security Council and after consultation with the appropriate regional bodies.
Article 48 - Execution of decisions
1. The measures necessary for the execution of the decisions of the Security Council for the maintenance of international peace and security shall be taken by all the Members of the United Nations or some of them, according to the appreciation of the Council.
2. These decisions are carried out by the Members of the United Nations directly and through their action in the appropriate international organizations of which they are members.
Article 49 - Support
The Members of the United Nations join together to lend each other mutual assistance in the execution of the measures adopted by the Security Council.
Article 50 - Post-embargo measures
If a State is the object of preventive or coercive measures taken by the Security Council, any other State, whether or not it is a Member of the United Nations, if it finds itself in the presence of particular economic difficulties due to the execution of the said measures, has the right to consult the Security Council on the solution of these difficulties.
Article 51 - Self-defense
Nothing in this Charter shall prejudice the inherent right of self-defence, individual or collective, in the event that a Member of the United Nations is the object of armed attack, 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-defence shall be immediately brought to the notice of the Security Council and shall in no way affect the power and the duty which the Council has under this Charter, to act at all times in such manner as it deems necessary to maintain or restore international peace and security.
Source: United Nations – the titles of the articles do not appear in the original text and are intended to facilitate reading