Treaties

The EU treaties are binding agreements between EU member countries. They set out EU objectives, rules for EU institutions, how decisions are made and the relationship between the EU and its member countries.

The creation of the European Coal and Steel Community (ECSC) was the starting point for over 50 years of European treaty-making.

The principal treaties are:

• Treaty establishing the European Coal and Steel Community (ECSC), signed in Paris in 1951. This treaty expired on 23 July 2002;
• Treaty establishing the European Economic Community (EEC), signed in Rome in 1957; and
• Treaty establishing the European Atomic Energy Community (Euratom), signed in Rome in 1957.

These treaties were amended by:

• the Merger Treaty, signed in Brussels in 1965;
• the Single European Act (SEA), signed in Luxembourg in 1986;
• the Treaty on European Union (EU Treaty or TEU), signed in Maastricht in 1992, when the EEC Treaty became the EC Treaty;
• the Treaty of Amsterdam, signed in 1997;
• the Treaty of Nice, signed in 2001.

Following difficulties in some EU countries in ratifying a European Constitutional Treaty signed in 2004, European leaders in 2007 agreed to convene an intergovernmental conference to finalise and adopt not a constitution but a ‘reform treaty’ for the EU.

The Lisbon Treaty, signed on 17 December 2007, was ratified by all EU countries and entered into force on 1 December 2009. It introduced changes to the existing treaties, and the EC Treaty became the Treaty on the Functioning of the EU (TFEU).

The founding treaties were also amended at the time of accession to membership of new countries in 1973 (Denmark, Ireland and the United Kingdom¹), in 1981 (Greece), in 1986 (Spain and Portugal), in 1995 (Austria, Finland and Sweden), in 2004 (Czech Republic, Estonia, Cyprus, Latvia, Lithuania, Hungary, Malta, Poland, Slovenia and Slovakia), in 2007 (Bulgaria and Romania) and in 2013 (Croatia).