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Invoking the EU’s Mutual Assistance Clause. What it says, what it means.

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The reaction of France to the terrorist attacks of Friday the 13th was invoking the EU’s mutual assistance clause. All EU member states expressed their unanimous and full support. But the question about the real meaning and consequences of this remain unclear for the majority, including the politicians. This commentary tries to give answers.

(Photo credit: Antonio Ponte, Flickr)



Invoking the EU’s Mutual Assistance Clause. What it says, what it means.

by Jochen Rehrl


‘France has been attacked. Europe as a whole has been attacked. Today France sought the help and assistance of all of Europe. And today Europe, united, responded yes.’
Federica Mogherini, EU High Representative for Foreign Affairs and Security Policy in the margins of the Foreign Affairs Council on 17 November 2015

Following the Paris attacks of 13 November 2015, French President François Hollande has invoked Article 42(7) of the Treaty of the European Union. This part of the Treaty, also known as the ‘mutual assistance clause’ (MAC), is little known to the public and is very rarely discussed in academic fora. Although the EU ‘Ministers expressed their unanimous and full support to France and their readiness to provide all the necessary aid and assistance’, the question about the real meaning and consequences of this remain unclear for the majority, including the politicians.

The roots of the MAC

The introduction of a mutual assistance clause in the Treaty framework of the European Union dates back to the process which should have led to a ‘Treaty establishing a Constitution for Europe’ (Article I-41(7)). The MAC was virtually unchanged by the ‘reflection phase’ that followed the negative referenda in France (May 2005) and the Netherlands (June 2005), and found its way into the Treaty of the European Union under Article 42(7), part of the intergovernmental structure of the Common Security and Defence Policy.

The wording: Stronger than in NATO, but more European

When the wording of Article 42(7) is compared with that of Article 5 of the North Atlantic Treaty, three main differences are obvious:

Motive: Article 5 of the North Atlantic Treaty is based on an armed attack against one or more NATO members. Article 42(7) can be invoked in case of armed aggression. In concrete terms, the blockade of a harbour by a warship would be armed aggression, but not an armed attack. Similarly, armed aggression does not necessarily need the ‘imminent threat’ of an attack, but preventive countermeasures could be taken. This interpretation would also be in line with the European Security Strategy of 2003, which advocates the development of ‘a strategic culture that fosters early, rapid, and when necessary, robust intervention’, in other words ‘preventive engagement’ in a comprehensive manner.

Area of responsibility: Article 5 of the North Atlantic Treaty limits itself to Europe, North America and other defined areas north of the tropic of cancer. The MAC of the Treaty of the European Union refers to ‘its territory’ and could therefore be seen as applicable world-wide due to the many overseas areas of the EU Member States. Taking the Falklands war in 1982 as an example, this war would not fall under Article 5 of NATO (south of the tropic of cancer), but could activate Article 42(7) of the Treaty of the European Union.

Means: Whereas Article 5 of the North Atlantic Treaty refers to assistance to ‘the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force’. With this wording, the Treaty allows the parties to decide on their assistance, from ‘diplomatic measures’ to ‘armed countermeasures’. The key words in this aspect are ‘as it deems necessary’ which gives the parties to the Treaty the possibility to decide on a national basis which action is appropriate and which one is not. According to the Treaty of the European Union, the Member States are obliged to provide ‘aid and assistance by all the means in their power’. Referring once again to the ESS 2003, ‘Dealing with terrorism may require a mixture of intelligence, police, judicial, military and other means.’ Hence no limitations or excuses for Member States (except Denmark with its general opt-out for military CSDP), not to provide full assistance and aid if requested.

A languages challenge

An interesting detail occurs when comparing the various language versions of Article 42(7) of the Treaty of the European Union. Some language versions talk about an ‘armed attack’ and some others about ‘armed aggression’ as the starting point for the mutual assistance clause. Here are some examples:

armed aggression armed attack
United Kingdom armed aggression Germany bewaffneter Angriff
France aggression armée Sweden väpnat angrepp
Italy aggressione armata Denmark væbnet angreb
Spain agresión armada Poland napa?ci zbrojnej
Portugal agressão armada Croatia ozbrojeného napadení


In case of differences between the various language versions, the version in which the negotiations were conducted will take precedence. Both the ‘Treaty establishing a Constitution for Europe’ and the ‘Treaty of the European Union’ were negotiated in French. Some comments were delivered in English. Hence, there is no doubt that ‘armed aggression’ should also be read by those EU Member States using ‘armed attack’ in their national interpretations.

Solidarity clause vs mutual assistance clause

The drafting of the Treaties of the European Union offers another possibility to request aid and assistance from the partners. In the ‘Treaty on the Functioning of the European Union’, Article 222 introduces a ‘Solidarity Clause’. This clause aims to create solidarity for preventive action and consequence management in cases of ‘natural and man-made disaster’ and ‘terrorist attacks’.

Concerning the relationship between the solidarity clause and the mutual assistance clause, there are three main differences: responsibility, area and tools.

Responsibility: When reading Article 222 of the TFEU, the sentence starts with ‘The Union and its Member States’ which clearly mirrors the prior responsibility of the Union. Conversely, the mutual assistance clause is embedded within the Common Foreign and Security Policy of the European Union and is therefore intergovernmental, led by the EU Member States with no Union responsibility.

Area: Whereas the solidarity clause is limited to the territory of the EU Member States, the mutual assistance clause within the CSDP, whilst it has possible political limitations, is not limited geographically.

Tools: Concerning the tools, both clauses refer to all available and appropriate means and assets, but the solidarity clause also refers to the instruments at the disposal of the Union which are not mentioned in the mutual assistance clause.

UN Charter is the foundation

The mutual assistance clause within the Treaty of the European Union is based on Article 51 of the UN Charter. The latter refers to the right of individual or collective self-defence as an inherent right. Article 51 constitutes an exception to the universal prohibition to use force (Article 2(4): ‘… Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state…’). This exception is legitimate ‘until the Security Council has taken measures necessary to maintain international peace and security’. According to Article 51 of the UN Charter, France has an obligation to report to the Security Council on its national action and action undertaken under Article 42(7) TEU together with its EU partners.

Conclusion: What to do

On 17 November 2015, the mutual assistance clause based on Article 42(7) TEU was activated by France and unanimously supported by the EU member states. The role of Denmark must be defined in the near future, when concrete action is requested.

By invoking the mutual assistance clause within the EU rather than appealing to NATO for assistance, France underlined its European approach to solving problems. For the EU Member States, this approach could be taken to overcome deadlocks in past and current crises both internal (e.g. the Greek debt and EU refugee crises) and external (e.g. Ukraine/Crimea).

If Syria has been identified as the key area in solving the terrorist challenge, the EU Member States should stand together and provide ‘aid and assistance by all means in their power’ without any hesitation. A failure to meet this obligation could cause lasting damage to the European Union. In my view, another inconclusive discussion about ‘the specific character of the security and defence policy of certain Member States’ as well as NATO’s role as ‘the foundation of the[ir] collective defence and the forum for its implementation’ should be avoided and replaced by concrete action, assistance and support.

In order to strengthen a certain kind of European ‘esprit de corps’, everyone should be reminded of Article 24(3) TEU: ‘The Member States shall support the Union’s external and security policy actively and unreservedly in a spirit of loyalty and mutual solidarity and shall comply with the Union’s action in this area.


Dr. Jochen Rehrl is a seconded national expert working for the European Security and Defence College within the European External Action Service of the European Union. His publications focus on foreign and security policy from a legal and political point of view.