The Treaty of Amsterdam created the formal possibility of a certain number of European Union (EU) Member States establishing an enhanced cooperation between themselves on matters covered by the Treaties, using the institutions and procedures of the European Union.
The Treaty of Nice facilitates the establishment of enhanced cooperation:
- the right of veto which the Member States enjoyed over the establishment of enhanced cooperation has disappeared (except in the field of foreign policy);
- the number of Member States required for launching the procedure has changed from the majority to the fixed number of eight Member States;
- its scope has been extended to the common foreign and security policy (CFSP).