Treaty of Nice
Adopted after the Nice European Council in December 2000 and signed on 26 February 2001, the Treaty of Nice entered into force on 1 February 2003.
It is the result of the Intergovernmental Conference (IGC) that began in February 2000, the objective of which was to adapt the working of the European institutions before the arrival of new Member States.
The Treaty of Nice opened the way to the institutional reform needed for the EU enlargement with the accession of countries from eastern and southern Europe. Some of its provisions were amended by the Treaty of Accession of the ten new Member States, which was signed in Athens in April 2003, and the Treaty of Luxembourg on the accession of Romania and Bulgaria, signed in April 2005. Since 1 January 2007, the date of the last enlargement, the Union has thus been founded on the EU and EC Treaties as most recently amended by the Treaties of Nice, Athens and Luxembourg.
The main changes made by the Treaty of Nice relate to limiting the size and composition of the Commission, extending qualified majority voting, a new weighting of votes within the Council and making the strengthened cooperation arrangements more flexible. The Declaration on the Future of the Union, annexed to the Treaty, sets out the next steps to be taken to deepen the institutional reforms and to make sure that the Treaty of Nice is just one stage in this process.
The draft Constitution, signed in September 2004, was conceived as an extension of the institutional reform process which started with the Treaty of Nice.
Following the difficulties in ratifying the Treaty in some Member States, the Heads of State and Government decided, at the European Council meeting on 16 and 17 June 2005, to launch a “period of reflection” on the future of Europe.
At the European Council meeting on 21 and 22 June 2007, European leaders reached a compromise and agreed to convene an IGC to finalise and adopt not a constitution but a “reform treaty” for the European Union. The Lisbon Treaty signed on 17 December 2007 entered into force on 1 December 2009.