What's In Blue

Arria-formula Meeting on Article 51 of the UN Charter

Tomorrow (24 February) there will be an open videoconference Arria-formula meeting on: “Upholding the collective security system of the UN Charter: the use of force in international law, non-state actors and legitimate self-defense”. The meeting, which is being organised by Mexico, will be livestreamed on the UN website (WebTV) from 3:00 – 6:00 p.m. Professor Naz K. Modirzadeh, the Director of the Harvard Law School Program on International Law and Armed Conflict, is the briefer. Security Council members will have the opportunity to make interventions, as will other UN member states, if time is available. All UN member states, permanent observer missions and non-governmental organisations are invited to attend the virtual meeting. Mexico intends to produce a chair’s summary of the meeting to reflect the views of the briefer and other speakers.

Article 51 of the UN Charter provides the legal basis for the use of force as a means of self-defence. It states:

Nothing in the present Charter shall impair the inherent right of individual or collective self-defence 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-defence 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.

The only other way, under the Charter, that force can be used is through a Security Council authorisation under article 42.

Mexico has circulated a concept note in preparation for the meeting. It states that the objective of the discussion is “to analyse the legal scope of Art. 51, in particular, the obligations derived from it, and to discuss the interpretation that has been given to this provision of the Charter against non-state actors, in particular in the context of counter-terrorism, and regarding the precedents that the aforementioned actions could set for other cases in the future”.

Since 2001, there has been an increase in instances of member states referencing article 51 in letters to the Security Council in order to justify the use of force against non-state actors such as terrorist groups. In the last few years, the majority of these letters have been on actions taken in response in Syria, Iraq, Libya and Yemen. For example, following a request from Iraq in September 2014 (S/2014/691) to help it combat the Islamic State in Iraq and the Levant (ISIL), a number of UN member states asserted their right to collective self-defence in support of “necessary and proportionate” military action against ISIL in Syria. More recently, Turkey cited article 51 in a letter to the Council in support of its operation in north-east Syria launched in October 2019, arguing that it was combating an “imminent terrorist threat” along its border posed by the Kurdistan Workers Party and other groups (S/2019/804) and stating that its response would be “proportionate, measured and responsible”.

Since 2019, Mexico has advocated the inclusion of an agenda item in the “Special Committee on the Charter of the United Nations and on the Strengthening of the Role of the Organization” (the Charter Committee) related to article 51. It appears that Mexico is keen to open up space for discussion of the implementation and interpretation of article 51 and its relationship with article 2(4) of the Charter. (Article 2(4) states: “All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.”)

The mandate of the Charter Committee, which is a subsidiary body of the General Assembly, is laid out in General Assembly resolution 70/117 (A/RES/70/117) of 14 December 2015. Among other tasks, the Committee is tasked with considering “all proposals concerning the question of the maintenance of international peace and security in all its aspects in order to strengthen the role of the United Nations” and deals with “the question of the implementation of the provisions of the Charter related to assistance to third States affected by the application of sanctions under Chapter VII of the Charter”.

In the concept note, Mexico poses a series of questions to help guide the discussion:

A number of substantive and procedural issues will be addressed during the meeting. The conversation will most likely reflect differing views on the circumstances under which it is appropriate to justify the use of force against non-state actors under article 51. Some members may emphasise the importance of upholding state sovereignty and the territorial integrity of UN member states in accordance with international law. Others may argue that states can justify the use of force against terrorist groups under article 51 when the host government is “unwilling or unable” to take action against them. There may also be discussion of the procedural aspects of article 51 notifications to the Security Council, including the contents of such notifications and whether and how the Council should reply to them. Some speakers may also call for a more efficient way of documenting such notifications so that they are easily accessible to the public.

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