DRAFT TREATY ON THE DEFENSE OF THE EUROPEAN UNION

At its informal meeting of 24 April 2026, the European Council – for the first time – agreed to initiate a debate on the modalities for implementing the so-called “mutual defence” clause provided for in Article 42(7) TEU.

This decision – although overdue – should be welcomed in light of the severity and vulnerability of Europe’s security situation in the current international context, both in the short and medium term.

However, it should be viewed within a broader context that includes – beyond the EU’s institutional framework – intergovernmental agreements between certain Member States and the European pillar of NATO.

Even a superficial analysis of these three defence frameworks reveals both useful complementarities and clear intrinsic limitations in each of them.

The main limitation is as follows: none of these frameworks possesses the characteristics inherent to a truly autonomous and operational defensive alliance. 

Such an alliance would, in fact, require the explicit conclusion – at the highest level and in the most solemn form – of a genuine Pact formalising the political, military, defensive and collective commitment of the signatory States.

In short, a new Treaty on the Defence of the European Union (TDEU), which could initially bring together the five largest military powers (E5: Germany, Spain, France, Italy, Poland).

“A carefully crafted European defence treaty would formalise and strengthen the commitment of the signatory States, thereby reinforcing the collective defence of the continent. Its primary virtue would be that of a robust declaration of solidarity, but also of a stronger commitment than a simple treaty provision that not all appear willing to apply."

JD Giuliani (https://www.jd-giuliani.eu)

Linked to the existing EU framework (CFSP, CSDP and, subsequently, the mutual defence clause), as well as to the NATO system, such an alliance would operate autonomously and, where necessary, in complementarity.

To be entirely concrete : in the event of a clear armed aggression against one of its members, the Alliance could respond collectively and as rapidly as possible, in accordance with the arrangements set out in the TDEU.

This idea has already been mentioned by several figures : Ms Merkel, Mr Borrell, Defence Commissioner Andrius Kubilius, among others (1).

Under current circumstances, it may appear less unrealistic than it once did.

And, since the « proof of the pudding is here in the drafting » - a « martyr » draft of the first introductory part of such a treaty is appended below.  

Jean-Guy Giraud 27 April 2026

https://www.lesamisdutraitedelisbonne.com

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(1) The Commission calls for a new intergovernmental treaty on defence. Defence Commissioner Andrius Kubilius called on Friday for the creation of a genuine European Defence Union:

“To achieve this, we need a new intergovernmental treaty,” the Commissioner argued.

The Defence Union could draw inspiration from the Schengen Agreement for police and judicial cooperation.

The idea was also supported in March by former High Representative Josep Borrell:

“If Europeans consider that they must unite to ensure their collective defence, they should consider creating a European Defence Union, based on a new ad hoc treaty and open to those willing to participate.”

20/04/2026

 "Draft Treaty on the Defence of the European Union" (First Part)

Preamble

Wishing to move further along the path of a common European defence and collectively possessing appropriate military capabilities, the signatory States have adopted the present Treaty:

Considering that:

• The progressive creation of a common European defence is part of the broader European project and of the integration process provided for in the Treaties – in particular Article 42(2) TEU;

• Significant progress has been made in this field, but a new step – in the form of a new Treaty on the Defence of the European Union – has become necessary in light of developments in the European and global geopolitical context;

• An integrated European defence requires a high level of collective political and military commitment, as well as adequate military capabilities;

• Certain EU Member States are ready to commit to this path immediately and may later be joined by others;

• In due course, this new step towards European defence may be incorporated into the framework of the EU Treaties;

• The provisions of this Treaty and the actions undertaken on its basis must remain compatible with EU Treaties, the North Atlantic Treaty, and the United Nations Charter.

The signatory States adopt the following provisions:

Article 1

The signatory States decide to form among themselves a defensive alliance, enabling them to take common strategic decisions and carry out joint military actions.

Article 2

The signatory States undertake to make available to the Alliance – in accordance with their respective capacities – all military means necessary for the implementation of these actions, under the modalities decided by the Security Council provided for in Article 3.

Article 3

Decisions and actions of the Alliance shall be taken by a Security Council composed of the Heads of State and Government of the signatory States – or the competent ministers.The Council shall meet at regular intervals or at the request of a signatory State.

Article 4

Joint military actions shall be prepared and implemented by a Military Committee, composed of the Chiefs of Staff of the signatory States.

Article 5

The objectives and actions of the Alliance shall remain compatible with those provided for in Title V, Section 2 TEU, in particular Article 42(7).The Alliance may call upon the assistance of EU bodies competent in defence matters.

Article 6

The Alliance shall take into account the commitments entered into by the signatory States within NATO.It may invite non‑EU States to participate in certain of its actions.

Article 7

The Alliance is intended to pave the way for an integrated European common defence within the meaning of Article 42(2) TEU.It shall remain open to the participation of other EU Member States willing to undertake the same commitments and possessing appropriate military capabilities."