Nordic Journal of International Law 73: 37–67, 2004. 37 © 2004 Koninklijke Brill NV. Printed in the Netherlands. Some Legal Issues Concerning the EU-NATO Berlin Plus Agreement MARTIN REICHARD* Max Planck Institute for Comparative Public Law and International Law, Heidelberg, Germany Abstract. The ‘Berlin Plus’agreement of 16 December 2002 now allows the EU to draw on some of NATO’s military assets in its own peacekeeping operations. The exact legal nature of the agreement, however, appears doubtful. Yet – given that political actors often resort to legal arguments in case of a dispute – the question of whether it is binding under international law is likely to be raised in the future. First, a short his- torical overview is given of the development of relations between the EU and NATO. In some respects, these are a mirror image of the co-operation NATO previously enter- tained with the Western European Union. However, since the French-British meeting of St-Mâlo these relations have assumed features of their own, for instance equal sta- tus for the EU. The text of the ‘Berlin Plus’agreement is then tested against the con- stitutive characteristics of a treaty in international law. In conclusion, the ‘Berlin Plus’is nothing but a non-binding agreement. The most important reason for this is that the EU manifestly lacked treaty-making competence, as the agreement was concluded by its High Representative for the Common Foreign and Security Policy, not by the statutory organ provided for in such cases in the Treaty on European Union. Nevertheless, as the parties proceed to implement the ‘Berlin Plus’according to its stated terms, legally binding force may arise for some of its contents through estoppel. 1. Introduction On 16 November 2002, at the Copenhagen European Council, the European Union (EU) and the North Atlantic Treaty Organisation (NATO) announced the conclusion of an agreement which allows the EU to draw on NATO owned mil- itary assets. The document had been signed a few days before by NATO’s Secretary-General George Robertson and the EU’s High Representative for the Common and Security Policy Javier Solana. In the future, the question whether this agreement 1 called the ‘Berlin Plus’ is legally binding could become very salient, whenever competing needs for NATO or US equipment or the ‘double-hatted’forces arise. 2 For example, if *The paper is part of my doctoral thesis project at the University of Vienna. 1 42 ILM 242 (2003). 2 The concept of double-hatted forces, governing the command status answerable to both the WEU and NATO, is part of the ‘Petersberg tasks’( see Western European Union Council of 38 MARTINREICHARD NATO wanted to engage in an international military operation against terror- ism, using its new NATO Response Force while the EU at the same time planned to engage in a peace-enforcement action in its near abroad, using the Rapid Reaction Force envisioned by the Helsinki European Summit in 1999. 3 The two organizations would then nd themselves competing for the same resources, rendering their operations mutually exclusive. In such a case, both actors would likely soon nd themselves reverting to legal arguments, as part of their strategies for achieving certain political goals. 4 The Berlin Plus agreement was instantly hailed by the press as a break- through in EU-NATO relations. Combined with the NATO-EU agreement on the Security of Information, concluded in March 2002, it opens the long- awaited possibility for the EU to engage in limited crisis management in its ‘near abroad’. 5 As its rst mission, the EU took over NATO’s peacekeeping operation ‘Amber Fox’in Macedonia, subsequently renamed ‘Operation Concordia’, on 1 April 2003. It is a rather small mission, manned with some 350 troops, commanded by NATO’s Deputy Supreme Allied Commander Europe Rainer Feist (a German Vice-Admiral). Soldiers from 27 countries are participating, half of them from outside the EU. However, should Operation Concordia work well, the EU stands ready to take over the United Nations mis- sion in Bosnia. 6 That mission will be substantially larger, in troop size require- ments as well as the complexity of its mandate. It includes continuing the work of nation-building, an area where the EU as an organization proper (i.e. apart from its member states) has as yet no experience. The essentials of this agreement had been prepared for a long time before, and it had been generally expected to be nalized in an international treaty between the two organizations. This article will address the question of its legal nature which is far from clear. After presenting the contents (2.), it will start with the history and back- ground of the present-day co-operation framework between the EU and NATO Ministers, Petersberg, Bonn, 19 June 1992, Declaration, II. para. 6. <www.cip. fuhem.es/ueh/ documentos/ueo/92-petersberg.htm>). These tasks were incorporated into the EU system by the Amsterdam Treaty, and are now found in Article 17(2) Treaty on European Union (hereinafter: TEU). 3 Cf. R. Rummel, ‘From Weakness to Power with the ESDP?’, 7 European Foreign Affairs Review (2002), p. 467. 4 Cf. I. Johnstone, ‘Security Council Deliberations: The Power of the Better Argument’, 14:3 EJIL (2003), pp. 437–480. 5 OJ EC, L80/36 of 27/7/2003. 6 European Council Summit Conclusions, Copenhagen, 12–13 December 2002, para. 29 (reprinted in J.-Y. Haine (ed.), ‘From Laeken to Copenhagen – European defence: core docu- ments’, Volume III, Chaillot Paper 57 (2003), Institute for Security Studies European Union, Paris (hereinafter: CP57), p. 170); Remarks by Javier Solana, following the establishment of EU-NATO permanent arrangements, 16 December 2002 (CP57, p. 180)..