The Mutual Assistance and Solidarity Clauses

Legal and Political Challenges of an Integrated EU Security System

by Antonio-Maria Martino (Author)
©2014 Thesis 129 Pages


The Mutual Assistance and Solidarity Clauses is the first comprehensive comparative analysis of two major innovations introduced by the Lisbon Treaty. Antonio-Maria Martino’s study focuses on the origins, scope, interpretation and technical aspects of both clauses, with a particular focus on the Solidarity Clause. He highlights the overlap between both provisions and the wide range of competences theoretically conferred upon the Union by the Solidarity Clause. The author also presents a critical outline of the negotiations with regard to the new Joint Proposal on the implementation of the Solidarity Clause by the Union, which will set out the framework for EU action in the event of a solidarity case.

Table Of Contents

  • Cover
  • Title
  • Copyright
  • About the author(s)/editor(s)
  • About the book
  • This eBook can be cited
  • Preface
  • The Mutual Assistance and Solidarity Clauses
  • Table of Contents
  • Summary
  • I. Introduction
  • II. Genesis
  • II.a. Working Group VIII ‘Defence’ of the European Convention
  • II.b. Provisions in the Constitution for Europe
  • II.b.i. The Mutual Assistance Clause
  • II.b.ii. The Solidarity Clause
  • II.c. European Council conclusions 2004
  • III. Models of the Mutual Assistance Clause
  • III.a. Article V Western European Union
  • III.b. Article 5 NATO Treaty
  • IV. Definition and Scope of the Mutual Assistance Clause
  • IV.a. Definition
  • IV.b. Territorial Scope
  • IV.c. Instruments
  • IV.d. Status of Neutral and Non-Aligned Member States
  • IV.e. Legal Status of the Mutual Assistance Clause
  • V. Definition and Scope of the Solidarity Clause
  • V.a. Definition
  • V.a.i. Article 222(1) TFEU
  • V.a.i.a. Terrorist Attack
  • V.a.i.b. Terrorist Threat
  • V.a.i.c. Natural Disaster
  • V.a.i.d. Man-Made Disaster
  • V.a.i.e. Forms of Assistance
  • V.a.i.f. Democratic Institutions and the Civilian Population
  • V.a.i.g. Political Authorities
  • V.a.ii. Article 222(2) TFEU
  • V.a.iii. Article 222(3) TFEU
  • V.a.iv. Article 222(4) TFEU
  • V.b. Instruments of the Union.
  • V.c. Legal Status of the Solidarity Clause
  • VI. Joint Proposal on the Implementation by the Union of the Solidarity Clause
  • VI.a. Content
  • VI.b. Recent Developments
  • VII. Relation between Article 42(7) TEU and Article 222 TFEU
  • VIII. Relation to Other Provisions in the Treaties
  • VIII.a. Relation to Article 122 TFEU
  • VIII.b. Relation to Article 196 TFEU
  • VIII.c. Relation to Article 214 TFEU
  • VIII.d. Relation to Articles 346–347 TFEU
  • IX. Concluding Remarks
  • X. Bibliography

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The ‘Mutual Assistance Clause’ (Article 42(7) TEU)1 and the ‘Solidarity Clause’ (Article 222 TFEU) were formally introduced by the Lisbon Treaty2. Whereas the Mutual Assistance Clause has models such as the NATO Treaty3 and the modified Brussels Treaty of 19544, which established the Western European Union (WEU), the Solidarity Clause is a ‘genuine’ innovation of the European Union. Although the overall aim – assistance to a Member State affected by an extraordinary situation – is the same and the principle of solidarity underpins both provisions, there are legal differences and also possible overlaps between the two Clauses.

According to Article 5 NATO Treaty, an armed attack against one of the signatories is to be considered an attack against them all. Therefore, in line with Article 51 of the UN Charter, such an attack would give rise to the right to self-defence for all NATO Member States. Furthermore, Article V WEU states that the signatories are to support the attacked State with all the military and other aid and assistance in their power. The Mutual Assistance Clause in Article 42(7) TEU applies in cases of armed aggression by a third State and is notable for its brevity, simplicity and vagueness. With regard to its legal setting, the Mutual Assistance Clause is not the object of a separate article itself but is covered by Article 42 TEU. The Clause does not include any reference to implementing procedures or to operational mechanisms, nor does it give any role to EU institutions.

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The Solidarity Clause is a unique horizontal provision striving to encompass and connect the intergovernmental ‘Common Foreign and Security Policy’ (CFSP) with supranational policy areas such as the ‘Area of Freedom, Security and Justice’ (AFSJ) and ‘Civil Protection’. It also has a possible military dimension, which makes it even more difficult to clearly set the limits of its scope. The Solidarity Clause is, therefore, a provision which aims at interlinking internal and external security. Despite the fact that the competent Working Group of the European Convention (Working Group VIII) proposed the Solidarity Clause as a complement to the Mutual Assistance Clause, the drafting of the former raises a number of legal and political questions. Unlike the Mutual Assistance Clause, Article 222(3) TFEU foresees the necessity to adopt an implementing provision in order to establish the arrangements for the implementation of the Solidarity Clause by the Union. The draft Council Decision (‘Joint Proposal’) that should set out this implementation is currently being discussed within the preparatory bodies of the Council. Due to its rather vague wording and its (geographic) scope, however, the Joint Proposal raises further legal questions.

The Mutual Assistance Clause and the Solidarity Clause are binding on all Member States, which are obliged to act in a spirit of solidarity. Both Clauses do not limit the assistance nor the means that can be applied to assist the affected Member State(s). Despite these similarities, they are separate in legal terms as the one clause has a clear intergovernmental background whereas the other is of a supranational nature. Certainly the supranationality of the Solidarity Clause does not prevent it from potentially extending its scope to intergovernmental areas such as defence and foreign policy. The intergovernmentalism of the Mutual Assistance Clause is absolute as no involvement of Union institutions is foreseen, whereas in the Solidarity Clause the Union is not only a direct addressee of the solidarity obligation, but has also a role (albeit a marginal one) as regards the Member States’ efforts in providing support to the affected Member State(s). Non-compliance with the obligation to assist arising out of Article 42(7) TEU does not result in any legal consequences. What is more, mandatory assistance is only binding on those Member States which are also NATO members, whereas the neutral and non-aligned Member States are, by ← 14 | 15 → and large, exempted from any obligation to assist. The Member State(s) that decide not to abide by the obligation established in the Solidarity Clause could incur in infringement proceedings before the Court of Justice of the European Union (CJEU). With respect to procedural issues, both Clauses are also very distinct: the Mutual Assistance Clause does not prescribe any procedure to be followed in the case of armed aggression; the Solidarity Clause refers to implementation arrangements which are still awaiting their final adoption. Even with regard to the assistance by the Member States, the Solidarity Clause refrains from limiting the freedom of the Member States and provides for a forum (the Council) where they are to coordinate themselves.

The following analysis focuses on the origins, scope, interpretation and technical aspects of the Mutual Assistance and Solidarity Clauses. It highlights the possible overlaps of both clauses and shows the wide range of competences theoretically conferred upon the Union and the Member States by the Solidarity Clause in particular. The paper gives also an outline on recent developments with regard to the so-called Joint Proposal which will implement Article 222(3) TFEU and set out the framework for Union action in a situation triggering the Solidarity Clause (‘solidarity case’).

1 Official Journal of the European Union C 326/1, ‘Consolidated Versions of the Treaty on European Union and the Treaty on the Functioning of the European Union’, 26.10.2012.

2 ‘Treaty of Lisbon amending the Treaty on European Union and the Treaty establishing the European Community’, UNTS I-47938.

3 ‘North Atlantic Treaty’ of 4 April 1949, 34 UNTS 243–246, available at http://www.nato.int/docu/basictxt/treaty.htm.

4 ‘Treaty between Belgium, France, Luxembourg, Netherlands and the United Kingdom of Great Britain and Northern Ireland for collaboration in economic, social and cultural matters and for collective self-defence’, UNTS I-304.


ISBN (Softcover)
Publication date
2014 (March)
Terrorismus polizeiliche Zusammenarbeit Zivilschutz Beistandsklausel Katastrophenschutz Sicherheitspolitik, Verteidigungspolitik
Frankfurt am Main, Berlin, Bern, Bruxelles, New York, Oxford, Wien, 2014. 129 pp.

Biographical notes

Antonio-Maria Martino (Author)

Antonio-Maria Martino studied law at the University of Vienna. He is Head of Unit in the Austrian Federal Ministry of the Interior and Head of Delegation in several EU Council committees. He is a lecturer at the University of Innsbruck and the author of several publications on international and EU law.


Title: The Mutual Assistance and Solidarity Clauses