Article 52 in Chapter VIII of the UN Charter can be considered the core of the cooperation between the UN and the EU:

As Tardy (2005: 50) and Graham and Felicio (2005: 91) point out, the EU is not a regional agency, but a sui generis regional organization, without legal personality. Given this, the EU represents the best example of collaboration with the UN according to this article, offering military and civilian tools through the implementation of the ESDP. Indeed, Secretary-General Boutros Boutros-Ghali (1992) admitted that the UN Charter:

2003 may be considered the watershed year in the relationship between the EU and the UN: before 2003 their co-operation was mainly based on high-level meetings and the exchange of information on the various activities involving the two organizations in common fields, such as development, aid for the poorest countries, and so on. However, both organizations were already reconsidering their relationship: on the one side, Secretary-General Kofi Annan was aware of the shortages that the UN was facing in the field of increasingly complex peacekeeping operations; on the other, Javier Solana, in his first act as High Representative for the Common Foreign and Security Policy (CFSP), sent out a strong signal speaking in front of the Security Council on 23 June 2000. Furthermore in September and

October 2000 meetings between the UN Security Council and the troika took place (Tardy 2005: 54). Then in 2003 the crisis in Iraq gave both organizations the opportunity to rethink their relationship on more concrete and strategic bases. In that year the European Security Strategy (ESS) document affirmed:

Through its clear recognition of the position of the UN, which has a pivotal role in the international system, the EU gives voice to binding expectations externally,1 and shows its strong willingness to offer its military and non-military resources to the UN. Furthermore, this formulation is spelled out in the ESS, which describes the EU as eager to take the initiative, especially in short-term crisis management, under the umbrella of the UN. In its conclusions in December 2003 (European Council 2003b: 11), the Council of the European Union clearly stated that the EU must take responsibility for acting globally in order to achieve an international order that can guarantee peace and security, also for its member states, in several areas: economic relations with other countries and organizations, political decisions with global impact, military intervention and peacekeeping operations.2