The Treaty of Economic, Social and Cultural Collaboration and Collective Self-Defence, signed in Brussels on 17 March 1948 by Belgium, France, Luxembourg, the Netherlands and the United Kingdom. It enters into force on 25 August 1948. Although this Treaty provides only for ‘cooperation’ between the contracting parties, ‘which will be effected through the Consultative Council referred to in Article VII’, and it does not provide for the establishment of an international organisation, in practice it leads to the creation of an organisation known as the ‘Brussels Treaty Organisation’ or ‘Western Union’.

The Brussels Treaty of 17 March 1948, modified and completed by the protocols signed in Paris on 23 October 1954 which enter into force on 6 May 1955. The Federal Republic of Germany and Italy accede to the modified Treaty. The ‘Consultative Council’ becomes the ‘Council of Western European Union’ (Article VIII), and the organisation established by the Treaty is renamed ‘Western European Union’ (WEU).

Statement made on 31 March 2010 by the Presidency of the Permanent Council of Western European Union (WEU) regarding the termination of the Modified Brussels Treaty and the closure of WEU (due to take place in June 2011). This statement follows the entry into force of the 2007 Treaty of Lisbon on 1 December 2009, particularly the mutual assistance clause between the Member States of the European Union (Article 42(7), EU Treaty).

Article J.4 of the Treaty on European Union, signed in Maastricht on 7 February 1992.

The Treaty on European Union, which entered into force on 1 November 1993, strengthens the role of Western European Union (WEU), defining it as an ‘integral part of the development of the European Union’ while preserving its institutional autonomy. Accordingly, WEU is given the task of drawing up and implementing decisions and actions which have defence implications.

Article 17 of the Treaty on European Union (EU) as amended by the Treaty of Amsterdam signed on 2 October 1997. Article 17 corresponds, in the intermediate numbering of the Treaty of Amsterdam, to Article J.7 of the EU Treaty (ex Article J.4).

Protocol on Article 17 of the Treaty on European Union (EU), annexed to the EU Treaty by the Treaty of Amsterdam. Article 17 corresponds, in the intermediate numbering of the Treaty of Amsterdam, to Article J.7 of the EU Treaty (ex Article J.4).

In the Declaration (No 3) annexed to the Final Act of the Treaty of Amsterdam, the Intergovernmental Conference notes the Declaration made by the Council of Ministers of Western European Union (WEU) on 22 July 1997 on the role of WEU and its relations with the European Union (EU) and the Atlantic Alliance. The latter Declaration refers particularly to Article 17 of the Treaty on EU (ex Article J.7) and the Protocol to this Article.

Article 17 of the Treaty on European Union as amended by the Treaty of Nice signed on 26 February 2001.

Table showing the evolution of the article in the Treaty on European Union (EU Treaty) which addresses the role of Western European Union (WEU) and its relations with the EU.

Article 42 of the Treaty on European Union (EU) as amended by the Treaty of Lisbon of 13 December 2007. According to the tables of equivalences annexed to the Treaty of Lisbon, Article 42 of the EU Treaty corresponds to the former Article 17 of the EU Treaty (and to Article 28 A in an intermediate numbering of the Treaty of Lisbon).

Protocol (No 11) on Article 42 of the Treaty on European Union (EU), annexed to the EU Treaty by the Treaty of Lisbon. According to the tables of equivalences annexed to the Treaty of Lisbon, Article 42 of the EU Treaty corresponds to the former Article 17 of the EU Treaty (and to Article 28 A in an intermediate numbering of the Treaty of Lisbon).