Treaty establishing the European Stability Mechanism, signed on 2 February 2012 in Brussels by the Heads of State or Government of the 17 Member States of the euro zone.

Le 25 mars 2011, le Conseil européen adopte la décision introduisant un nouveau paragraphe à l'article 136 du traité sur le fonctionnement de l'Union européenne. Cette modification, adoptée sur la base de l'article 48, paragraphe 2, du traité sur l'Union européenne, définit les conditions à respecter par les Etats membres de la zone euro pour la conclusion du traité établissant un mécanisme européen de stabilité.

On 17 March 2011, following a request from the European Council, the European Central Bank delivers an opinion on the draft European Council Decision amending Article 136 of the Treaty on the Functioning of the European Union with regard to a stability mechanism for Member States whose currency is the euro.

At the European Council on 24 and 25 March 2011, the Heads of State or Government welcome the decisions taken on 11 March by the Heads of State or Government of the euro area and approve the structural features of the European Stability Mechanism.

On 21 March 2011, Jean-Claude Juncker, President of the Eurogroup, outlines the substance of the agreement secured between the euro zone finance ministers on the funding of the European Stability Mechanism and the actions that it could lead to in terms of financial assistance.

On 11 July 2011, a first Treaty establishing the European Stability Mechanism was signed in Brussels by the 17 Member States in the euro area. The deterioration of the financial situation in Greece meant that a new aid plan was required, involving the Member States in the euro area, the financial assistance instruments set up in 2010 (the European Financial Stabilisation Mechanism, including the European Financial Stability Facility (EFSF)) and private creditors. Given the risk of contagion, the decision was taken to review the financial assistance instruments, namely the EFSF and the recently approved European Stability Mechanism. The Treaty of 11 July 2011 did not enter into force; it was amended and served as the basis for another Treaty establishing the European Stability Mechanism, signed in Brussels on 2 March 2012.

At their meeting on 26 October 2011 in Brussels, the Heads of State or Government of the Member States of the euro zone manage, after tough negotiations, to adopt a comprehensive package to enable the euro zone to improve its resistance to the sovereign debt crisis and to finalise a second programme of aid to Greece, mainly based on measures to bring the Greek debt down to a sustainable level.

Annexed to the conclusions of the European Council, held on 8 and 9 December 2011, the statement adopted by the Heads of State or Government affirms their determination to move towards a stronger economic union by means of a new fiscal compact and strengthened economic policy coordination as well as the development of stabilisation tools to face short-term challenges.