The United Nations was founded in 1948 and now assembles 189 countries. France and the UK are permanent members of the UN Security Council. The EU is not a member of the Security Council in its own right.
Although the UN Charter requires a UN mandate for the use of military forces, the EU does not provide for such a mandate in its Common Security and Defence Policy.
The future
The EU EU Constitution proposes that EU members of the Security Council should co-ordinate their positions, eventually taking UN decisions by qualified majority voting in the Council, after unanimous agreement at an EU Summit.Links
http://www.un.org/