
The
European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
(EU) and the
North Atlantic Treaty Organisation
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two Nor ...
(NATO) are two main treaty-based
Western
Western may refer to:
Places
*Western, Nebraska, a village in the US
* Western, New York, a town in the US
*Western Creek, Tasmania, a locality in Australia
*Western Junction, Tasmania, a locality in Australia
*Western world, countries that i ...
organisations for cooperation between member states, both headquartered in
Brussels
Brussels (french: Bruxelles or ; nl, Brussel ), officially the Brussels-Capital Region (All text and all but one graphic show the English name as Brussels-Capital Region.) (french: link=no, Région de Bruxelles-Capitale; nl, link=no, Bruss ...
, Belgium. Their natures are different and they operate in different spheres: NATO is a purely intergovernmental organisation functioning as a military alliance, which serves to implement article 5 of the
North Atlantic Treaty
The North Atlantic Treaty, also referred to as the Washington Treaty, is the treaty that forms the legal basis of, and is implemented by, the North Atlantic Treaty Organization (NATO). The treaty was signed in Washington, D.C., on 4 April 194 ...
on collective territorial defence. The EU on the other hand is a partly supranational and partly intergovernmental ''sui generis'' entity akin to a
confederation
A confederation (also known as a confederacy or league) is a union of sovereign groups or states united for purposes of common action. Usually created by a treaty, confederations of states tend to be established for dealing with critical issu ...
that entails wider economic and political
integration
Integration may refer to:
Biology
* Multisensory integration
* Path integration
* Pre-integration complex, viral genetic material used to insert a viral genome into a host genome
*DNA integration, by means of site-specific recombinase technolo ...
. Unlike NATO, the EU pursues a
foreign policy
A state's foreign policy or external policy (as opposed to internal or domestic policy) is its objectives and activities in relation to its interactions with other states, unions, and other political entities, whether bilaterally or through ...
in its own right—based on consensus, and member states have equipped it with tools in the field of defence and crisis management; the
Common Security and Defence Policy
The Common Security and Defence Policy (CSDP) is the European Union's (EU) course of action in the fields of defence and crisis management, and a main component of the EU's Common Foreign and Security Policy (CFSP).
The CSDP involves the dep ...
(CSDP)
structure.
The memberships of the EU and NATO are distinct, and some EU member states are traditionally neutral on defence issues. The EU and NATO have respectively
27 and
31 member states, of which 22 are members of both. Another four NATO members are EU applicants—Albania, Montenegro, North Macedonia, and Turkey—and another one, the United Kingdom, is a
former EU member. Iceland and Norway have opted to remain outside of the EU, but do participate in the
European Single Market as part of their
European Economic Area
The European Economic Area (EEA) was established via the ''Agreement on the European Economic Area'', an international agreement which enables the extension of the European Union's single market to member states of the European Free Trade Ass ...
(EEA) membership. EU member Sweden has applied to NATO and is being ratified as a member, leaving four non-NATO states in the EU: Austria, Cyprus, Ireland, and Malta. Several EU and NATO member states were formerly members of the
Warsaw Pact
The Warsaw Pact (WP) or Treaty of Warsaw, formally the Treaty of Friendship, Cooperation and Mutual Assistance, was a collective defense treaty signed in Warsaw, Poland, between the Soviet Union and seven other Eastern Bloc socialist republi ...
.
The EU has its own mutual defence clause in Articles 42(7) and 222 of the
Treaty on European Union
The Treaty on European Union (2007) is one of the primary Treaties of the European Union, alongside the Treaty on the Functioning of the European Union (TFEU). The TEU form the basis of EU law, by setting out general principles of the EU's ...
(TEU) and the
Treaty on the Functioning of the European Union
The Treaty on the Functioning of the European Union (TFEU) is one of two treaties forming the constitutional basis of the European Union (EU), the other being the Treaty on European Union (TEU). It was previously known as the Treaty Establishi ...
(TFEU), respectively. The
CSDP command and control structure is however much smaller than the
NATO Command Structure
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two Nor ...
(NCS), and the extent to which the CSDP should evolve to form a full defence arm for the EU that is able to implement the EU mutual defence clause in its own right is a point of contention, and the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
(UK) has objected to this. At the UK's insistence in the negotiations leading to the
Treaty of Lisbon
The Treaty of Lisbon (initially known as the Reform Treaty) is an international agreement that amends the two treaties which form the constitutional basis of the European Union (EU). The Treaty of Lisbon, which was signed by the EU member s ...
, Article 42.2 of TEU also specifies that
NATO
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
shall be the main forum for the implementation of collective self-defence for EU member states that are also NATO members.
The 2002
Berlin Plus agreement
The Berlin Plus agreement is the short title of a comprehensive package of agreements made between NATO and the EU on 16 December 2002.NATO, ''Berlin Plus agreement'', June 21, 2006. These agreements were based on conclusions of NATO's 1999 Wash ...
and 2018 Joint Declaration provide for cooperation between the EU and NATO, including that that NCS resources may be used for the conduct of the EU's CSDP missions.
History
1948–1951: Common origins, where NATO cannibalises intra-European initiatives
The
Western Union
The Western Union Company is an American multinational financial services company, headquartered in Denver, Colorado.
Founded in 1851 as the New York and Mississippi Valley Printing Telegraph Company in Rochester, New York, the company ch ...
, established to implement the 1948
Treaty of Brussels
The Treaty of Brussels, also referred to as the Brussels Pact, was the founding treaty of the Western Union (alliance), Western Union (WU) between 1948 and 1954, when it was amended as the Modified Brussels Treaty (MTB) and served as the foundin ...
signed by Belgium, France, the Netherlands, Luxembourg, and the United Kingdom, represents a precursor to both NATO and the EU's defence arm, the
Common Security and Defence Policy
The Common Security and Defence Policy (CSDP) is the European Union's (EU) course of action in the fields of defence and crisis management, and a main component of the EU's Common Foreign and Security Policy (CFSP).
The CSDP involves the dep ...
(CSDP).
1954: Failure to establish an autonomous European pillar in NATO
Had its founding treaty not failed to acquire ratification in the French Parliament in 1954, the European Defence Community would have entailed a pan-European military, divided into national components, and had a common budget, common arms, centralized military procurement, and institutions. The EDC would have had an integral link to NATO, forming an autonomous European pillar in the Atlantic alliance.
1996–present: Tensions and mutual interests as EU gains autonomous defence structures
Following the establishment of the ESDI and the St. Malo declaration,
US Secretary of State
The United States secretary of state is a member of the executive branch of the federal government of the United States and the head of the U.S. Department of State. The office holder is one of the highest ranking members of the president's C ...
Madeleine Albright
Madeleine Jana Korbel Albright (born Marie Jana Korbelová; May 15, 1937 – March 23, 2022) was an American diplomat and political scientist who served as the 64th United States secretary of state from 1997 to 2001. A member of the Democratic ...
were among others who voiced concern that an independent European security pillar could undermine NATO, as she put forth the three famous D's:
Eastern enlargement
Present cooperation

The
Berlin Plus agreement
The Berlin Plus agreement is the short title of a comprehensive package of agreements made between NATO and the EU on 16 December 2002.NATO, ''Berlin Plus agreement'', June 21, 2006. These agreements were based on conclusions of NATO's 1999 Wash ...
enables
EU operations to be planned and conducted at the military strategic and operational level with recourse to assets and capabilities in the
NATO Command Structure
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two Nor ...
(NCS). In such an event, an Operational Headquarters (OHQ) would be set up within NATO's
Supreme Headquarters Allied Powers Europe
Supreme Headquarters Allied Powers Europe (SHAPE) is the military headquarters of the North Atlantic Treaty Organization's (NATO) Allied Command Operations (ACO) that commands all NATO operations worldwide. ACO's and SHAPE's commander is t ...
(SHAPE) in Mons, Belgium. SHAPE is the main headquarters of
Allied Command Operations
Allied Command Operations (ACO) is one of the two strategic commands of the North Atlantic Treaty Organization (NATO), the other being Allied Command Transformation (ACT). The headquarters and commander of ACO is Supreme Headquarters Allied Po ...
(ACO).
When the NCS provides the OHQ, the
Deputy Supreme Allied Commander Europe
The Supreme Allied Commander Europe (SACEUR) is the commander of the North Atlantic Treaty Organization's (NATO) Allied Command Operations (ACO) and head of ACO's headquarters, Supreme Headquarters Allied Powers Europe (SHAPE). The commander is ...
(DSACEUR) acts as Operation Commander (OpCdr).
The Berlin Plus agreement requires that the use of NATO assets by the EU is subject to a "right of first refusal", i.e. NATO must first decline to intervene in a given crisis, and contingent on unanimous approval among NATO states, including those outside of the EU. For example, Turkish reservations about
Operation Concordia EUFOR Concordia was a European Union (EU) peacekeeping mission in the Republic of North Macedonia, which started on 31 March 2003. The EU took over from NATO's operation Allied Harmony and deployed around 300 troops to provide security to EU and ...
using NATO assets delayed its deployment by more than five months.
[Bram Boxhoorn, ''Broad Support for NATO in the Netherlands'', 21-09-2005, ]
The
European External Action Service
The European External Action Service (EEAS) is the diplomatic service and combined foreign and defence ministry of the European Union (EU). The EEAS is led by the High Representative for Foreign Affairs and Security Policy (HR/VP), who is a ...
's (EEAS)
Military Staff
A military staff or general staff (also referred to as army staff, navy staff, or air staff within the individual services) is a group of officers, enlisted and civilian staff who serve the commander of a division or other large military ...
(EUMS), situated in the
Kortenberg building
, former_names =
, alternate_names =
, image = 150kortenberg.jpg
, alt =
, caption =
, altitude =
, building_type = Office building
, architectural_style = ...
in Brussels, has a permanent NATO liaison team and runs a permanent EU cell at NATO's
Supreme Headquarters Allied Powers Europe
Supreme Headquarters Allied Powers Europe (SHAPE) is the military headquarters of the North Atlantic Treaty Organization's (NATO) Allied Command Operations (ACO) that commands all NATO operations worldwide. ACO's and SHAPE's commander is t ...
(SHAPE) in
Mons
Mons (; German and nl, Bergen, ; Walloon and pcd, Mont) is a city and municipality of Wallonia, and the capital of the province of Hainaut, Belgium.
Mons was made into a fortified city by Count Baldwin IV of Hainaut in the 12th century. ...
.
Comparison
Command structures
The CSDP entails
collective self-defence amongst member states. This responsibility is based on Article 42.7 of TEU, which states that this responsibility does not prejudice the specific character of the security and defence policy of certain member states, referring to policies of neutrality. See
Neutral country§European Union for discussion on this subject. According to the
Article 42.7 "If a Member State is the victim of armed aggression on its territory, the other Member States shall have towards it an obligation of aid and assistance by all the means in their power, in accordance with Article 51 of the United Nations Charter. This shall not prejudice the specific character of the security and defence policy of certain Member States." Article 42.2 furthermore specifies that
NATO
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
shall be the main forum for the implementation of collective self-defence for EU member states that are also NATO members.
The EU does not have a permanent military command structure similar to the
North Atlantic Treaty Organization
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
's (NATO)
Allied Command Operations
Allied Command Operations (ACO) is one of the two strategic commands of the North Atlantic Treaty Organization (NATO), the other being Allied Command Transformation (ACT). The headquarters and commander of ACO is Supreme Headquarters Allied Po ...
(ACO), although it has been agreed that ACO resources may be used for the conduct of the EU's CSDP missions under the
Berlin Plus agreement
The Berlin Plus agreement is the short title of a comprehensive package of agreements made between NATO and the EU on 16 December 2002.NATO, ''Berlin Plus agreement'', June 21, 2006. These agreements were based on conclusions of NATO's 1999 Wash ...
. The
Military Planning and Conduct Capability
The Military Planning and Conduct Capability (MPCC) is a permanent operational headquarters (OHQ) at the military strategic level for military operations of up to 2500 troops (i.e. the size of one battle group) deployed as part of the Common Se ...
(MPCC), established in 2017 and to be strengthened in 2020, does however represent the EU's first step in developing a permanent military OHQ. In parallel, the newly established
European Defence Fund
The European Defence Fund (EDF) is a component of the European Union's (EU) Common Security and Defence Policy (CSDP) which aims to coordinate and increase national investment in defence research and improve interoperability between national armed ...
(EDF) marks the first time the
EU budget
The Budget of the European Union (EU budget) is used to finance EU funding programmes (such as the European Regional Development Fund, the Cohesion Fund, Horizon Europe, or Erasmus+) and other expenditure at the European level.
The EU budge ...
is used to finance multinational defence projects.
European Union
NATO
Membership

The memberships of the EU and NATO are distinct. The EU and NATO have respectively
27 and
31 member states, of which 22 states are members of both.
The five EU member states which are not members of NATO (
Austria
Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...
,
Cyprus
Cyprus ; tr, Kıbrıs (), officially the Republic of Cyprus,, , lit: Republic of Cyprus is an island country located south of the Anatolian Peninsula in the eastern Mediterranean Sea. Its continental position is disputed; while it is ...
,
Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
,
Malta
Malta ( , , ), officially the Republic of Malta ( mt, Repubblika ta' Malta ), is an island country in the Mediterranean Sea. It consists of an archipelago, between Italy and Libya, and is often considered a part of Southern Europe. It lies ...
and
Sweden) held positions of
neutrality
Neutral or neutrality may refer to:
Mathematics and natural science Biology
* Neutral organisms, in ecology, those that obey the unified neutral theory of biodiversity
Chemistry and physics
* Neutralization (chemistry), a chemical reaction ...
during the Cold War, which they have since maintained. However, all but Cyprus are now members of NATO's
Partnership for Peace
The Partnership for Peace (PfP; french: Partenariat pour la paix) is a North Atlantic Treaty Organization (NATO) program aimed at creating trust between the member states of NATO and other states mostly in Europe, including post-Soviet states; ...
. Cyprus is the only EU member state that is neither a full member of NATO nor participates in the Partnership for Peace. Any treaty concerning Cyprus' participation in NATO would likely be blocked by
Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
because of the
Cyprus dispute
The Cyprus problem, also known as the Cyprus dispute, Cyprus issue, Cyprus question or Cyprus conflict, is an ongoing dispute between Greek Cypriots in the south and Turkish Cypriots in the north. Initially, with the occupation of the island ...
.
The
2022 Russian invasion of Ukraine reignited debate surrounding NATO membership in several countries, with Finland and Sweden both applying for NATO membership.
Of the 31 NATO member states, 29 are European states. The 7 European states which are NATO members but not EU members includes four states that have applied for EU membership (Albania, Montenegro, North Macedonia, and Turkey), as well as the United Kingdom which is a
former EU member. The two others—Iceland and Norway—have opted to remain outside of the EU, however participate in the
EU's single market.
Several EU member states were formerly members of the NATO rival
Warsaw Pact
The Warsaw Pact (WP) or Treaty of Warsaw, formally the Treaty of Friendship, Cooperation and Mutual Assistance, was a collective defense treaty signed in Warsaw, Poland, between the Soviet Union and seven other Eastern Bloc socialist republi ...
.
See also
*
Foreign relations of the European Union
Although there has been a large degree of integration between European Union member states, foreign relations is still a largely intergovernmental matter, with the 27 members controlling their own relations to a large degree. However, with th ...
*
Foreign relations of NATO
NATO (the North Atlantic Treaty Organization) maintains foreign relations with many non-member countries across the globe. NATO runs a number of programs which provide a framework for the partnerships between itself and these non-member nations, ...
*
European Union–United States relations
*
Council of Europe–European Union relations
Council of Europe–European Union relations are the bilateral relations between the Council of Europe and the European Union. The Council of Europe and the European Union have shared relations since 1992. Almost 180 programmes have been impleme ...
*
Canada–European Union relations
Relations between Canada and the European Union (EU) and its forerunners date back to the 1950s. While the relationship is primarily an economic one, there are also matters of political cooperation. Canadians also use English and French — both ...
*
Iceland–European Union relations
Iceland is heavily integrated into the European Union via the Agreement on the European Economic Area and the Schengen Agreement, despite its status as a non- EU member state. Iceland applied for membership in 2009 but the application was contro ...
*
Norway–European Union relations
Norway is not a member state of the European Union (EU). However, it is associated with the Union through its membership of the European Economic Area (EEA), signed in 1992 and established in 1994. Norway was a founding member of the European Fre ...
*
Turkey–European Union relations
Relations between the European Union (EU) and Turkey were established in 1959, and the institutional framework was formalised with the 1963 Ankara Agreement. Albeit not officially part of the European Union, Turkey is one of the EU's main part ...
*
Ukraine–European Union relations
Relations between the European Union (EU) and Ukraine are shaped through the Ukraine–European Union Association Agreement and the Deep and Comprehensive Free Trade Area (DCFTA). Ukraine is a priority partner within the Eastern Partnership and ...
*
United Kingdom–European Union relations
*
Austria–NATO relations
Republic of Austria, Austria and the NATO, North Atlantic Treaty Organization (NATO) have a close relationship. Austria with Ireland, Cyprus and Malta are the only members of the European Union that are not members of NATO. Austria has had for ...
*
Cyprus–NATO relations
Cyprus is one of four European Union (EU) member states which is not a member of the North Atlantic Treaty Organization (NATO), and the only one not to participate in NATO's Partnership for Peace (PfP) program.
The others are Austria, Ire ...
*
Finland–NATO relations
The Republic of Finland and the North Atlantic Treaty Organization (NATO) have a close relationship. Finland is one of six members of the European Union that are not members of NATO. Finland has had formal relations with NATO since 1994, ...
*
Ireland–NATO relations
*
Malta–NATO relations
Malta and the North Atlantic Treaty Organization (NATO) have a close relationship. Malta is one of four members of the European Union that are not members of NATO, the others being Austria, Cyprus and Ireland. Malta has had formal relations ...
*
Sweden–NATO relations
The Kingdom of Sweden and the North Atlantic Treaty Organization (NATO) have a close relationship and regularly carry out joint exercises, cooperate in peacekeeping operations and share information. Sweden is one of six members of the European ...
*
Ukraine–NATO relations
Relations between Ukraine and the North Atlantic Treaty Organization (NATO) started in 1992. Ukraine applied to integrate with a NATO Membership Action Plan (MAP) in 2008. Plans for NATO membership were shelved by Ukraine following the 2010 pr ...
*
Brexit
Brexit (; a portmanteau of "British exit") was the withdrawal of the United Kingdom (UK) from the European Union (EU) at 23:00 GMT on 31 January 2020 (00:00 1 February 2020 CET).The UK also left the European Atomic Energy Community (EAE ...
*
Western European Union
The Western European Union (WEU; french: Union de l'Europe occidentale, UEO; german: Westeuropäische Union, WEU) was the international organisation and military alliance that succeeded the Western Union (WU) after the 1954 amendment of the 1948 ...
*
European Union as a potential superpower
A potential superpower is a state or a political and economic entity that is speculated to be—or to have the potential to soon become—a superpower.
Currently, only the United States fulfills the criteria to be considered a superpower. H ...
*
Enlargement of the European Union
The European Union (EU) has expanded a number of times throughout its history by way of the accession of new member states to the Union. To join the EU, a state needs to fulfil economic and political conditions called the Copenhagen criteria ...
*
Enlargement of NATO
NATO is a military alliance of twenty-eight European and two North American countries that constitutes a system of collective defense. The process of joining the alliance is governed by Article 10 of the North Atlantic Treaty, which allows ...
*
European army
The Common Security and Defence Policy (CSDP) is the European Union's (EU) course of action in the fields of defence and crisis management, and a main component of the EU's Common Foreign and Security Policy (CFSP).
The CSDP involves the deplo ...
*
Neutral member states in the European Union
The European Union (EU) is an institution of its own kind consisting of member states being part of an alliance as well as military neutral member states while developing a Common Foreign and Security Policy for the union as a whole. The military ...
*
Strategic autonomy Strategic autonomy is defined as the ability of a state to pursue its national interests and adopt its preferred foreign policy without depending heavily on other foreign states.
In European context, strategic autonomy is the ability of the Europe ...
*
Neutral and Non-Aligned European States
Neutral and Non-Aligned European States, sometimes known by abbreviation NN states, was a Cold War era informal grouping of states in Europe which were neither part of NATO nor Warsaw Pact but were either neutral or members of the Non-Aligne ...
References
External links
NATO article on EU relationsEU factsheets on NATO relationsEDC Treaty (unofficial translation) see pg 2EDC information on European NavigationNATO AND THE EUROPEAN UNION: A DEFENSIVE RELATIONSHIP
{{DEFAULTSORT:NATO realtions
NATO
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
Transatlantic relations
NATO relations
Foreign relations of the European Union