NATO’s maritime activities

  • Last updated: 03 Aug. 2023 12:21

The world’s oceans connect us. They are essential to global commerce and our way of life. Today, shipping makes up 90 per cent of all international trade in raw material and manufactured goods, and tankers carry more than half of the world’s oil. NATO is committed to strengthening the Alliance’s posture and situational awareness to deter and defend against all threats in the maritime domain. This includes upholding freedom of navigation, securing maritime trade routes and protecting the Alliance’s main lines of communications and choke points, as well as securing supplies and reinforcements along transatlantic routes during crisis and conflict.


  • NATO's 2022 Strategic Concept, the Alliance's overarching strategy document, describes maritime security as the "key to our peace and prosperity". As such, NATO's maritime activities cover all three of the Alliance's core tasks: deterrence and defence, crisis prevention and management, and cooperative security.
  • NATO's Standing Naval Forces (SNF) provide the Alliance with a continuous, credible and agile maritime capability that can be rapidly deployed in times of crisis or tension. Since Russia's full-scale invasion of Ukraine in February 2022, the SNF have been strategically deployed to strengthen the Alliance's maritime posture.
  • NATO is currently carrying out Operation Sea Guardian (OSG) in the Mediterranean Sea. OSG maintains a safe and secure maritime environment through maritime security capacity-building, situational awareness and counter-terrorism.
  • Under its Aegean Activity, NATO is providing support to broader international efforts with regards to the refugee and migrant crisis in the Aegean Sea.
  • Coordination and cooperation with partner countries, including through NATO's maritime and joint exercise programme, increases interoperability and improves core warfighting competencies, demonstrating credible deterrence in the maritime domain.
  • NATO also cooperates with the United Nations and the European Union, as well as with other regional organisations, such as the Organization for Security and Co-operation in Europe and the African Union, in the maritime domain.



The Alliance Maritime Posture

The maritime domain encompasses oceans and seas – including everything on, above and below the surface, in all directions. It forms a continuum with other operational domains (land, air, space and cyberspace).

The Alliance Maritime Posture describes NATO's capabilities and functions in the maritime domain, and how it uses its naval forces to support the Alliance's three core tasks: deterrence and defence, crisis prevention and management, and cooperative security.

The Alliance's naval forces are composed of maritime forces, sensors and other capabilities that contribute to Alliance security. The Alliance Maritime Posture relies on these forces to perform the following three functions:

Strategic function: The presence of maritime forces creates strategic and deterrent effects, including for assurance and messaging, and demonstrates NATO's intent to operate as required. The flexibility of maritime forces provides nearly instant availability of inherently tailorable force packages yielding a range of measured and viable political and military options.

Security function: NATO maintains a safe and secure maritime environment through a range of maritime security operations and/or activities. Maritime forces provide a ready and flexible mechanism and significant versatility for a broad range and scale of missions and tasks.

Warfighting function: In the event of a conflict, maritime forces can rapidly transition from low-intensity to high-intensity missions and tasks. Surface, sub-surface and above-surface capabilities and forces can work together to exercise sea denial or control, support reinforcement, protect assets, project power and support joint forces and joint effects.


Strengthening NATO's maritime posture in response to Russia's war in Ukraine

Since Russia's illegal annexation of Crimea in 2014, the Alliance has adapted and strengthened its deterrence and defence posture across all domains. In response to Russia's full-scale invasion of Ukraine in February 2022, NATO activated its Graduated Response Plans and deployed high-readiness elements of the NATO Response Force (NRF) for the first time in a deterrence and defence role – including the activation of the Standing Naval Forces, which are part of the NRF's Very High Readiness Joint Task Force (VJTF).

Since February 2022, NATO has stepped up its vigilance activities – including an increased presence of Allied aircraft carriers in the Baltic, Adriatic and Mediterranean Seas, and the deployment of multiple Carrier Strike Groups – to ensure appropriate strategic awareness and force readiness. By leveraging a deliberate rhythm of military activity across all geographic areas of the Alliance, as well as across all operational domains and functional areas, multi-carrier deployments demonstrate Allied resolve to protect NATO populations and defend every inch of Allied territory – including Allied territorial waters – at all times.

Through maritime exercises, NATO Allies and partners are maintaining and developing warfighting competencies, building interoperability between their forces as well as improving their overall combined maritime skills and readiness for all operations, international and national. Some areas and competencies being incorporated into exercises include: high-end warfighting capacities, such as the protection of sea lines of communication, rapid reinforcement, amphibious operations, anti-submarine warfare, land attack, deep-precision strike, and integrated air and missile defence; countering hybrid threats in the maritime domain; defending against threats in cyber space; and countering threats against carrier strike groups.


NATO's Standing Naval Forces

The Standing Naval Forces (SNF) are a core maritime capability of the Alliance, and a centrepiece of its maritime posture. Under NATO operational control, they provide the Alliance with a continuous, credible and agile maritime capability that can be rapidly deployed in times of crisis or tension. The SNF are a multinational deterrent force that can provide a rapid response to defend against any potential adversary, and contribute to crisis management, security cooperation with partners and maritime security. They carry out a programme of scheduled exercises, manoeuvres and port visits. They also conduct joint training exercises with NATO partners to enhance interoperability.

NATO's SNF consist of four groups: the Standing NATO Maritime Groups (SNMG1 and SNMG2) and the Standing NATO Mine Countermeasures Groups (SNMCMG1 and SNMCMG2). All four Groups are part of the NATO Response Force (NRF), the Alliance's rapid-reaction force, through the VJTF(M), its maritime component. They operate in the Atlantic Ocean and in the Baltic, North, Mediterranean and Black Seas, covering the entire maritime area of responsibility of NATO.


The Standing NATO Maritime Groups are multinational, integrated maritime forces made up of frigates or destroyers from various Allied countries, supported by a replenishment vessel. These vessels are permanently available to NATO to perform different tasks ranging from exercises to support of operations. They also help to establish Alliance presence, demonstrate solidarity, conduct routine diplomatic visits to different countries, support partner engagement and provide a variety of maritime military capabilities to ongoing operations.

SNMG1 and SNMG2 function according to the operational needs of the Alliance, therefore helping to maintain optimal flexibility.

As part of NATO's Standing Naval Forces, SNMG1 and SNMG2 fall under the authority of the Supreme Allied Commander Europe (SACEUR). In December 2012, Allied Maritime Command (MARCOM) became the operational hub for all Alliance maritime operations. As such, authority and operational command over the SNMGs are generally delegated to MARCOM.

Located in Northwood, United Kingdom, MARCOM also hosts the NATO Shipping Centre (NSC), which is the link between NATO and the merchant shipping community. Permanently manned by NATO, the NSC is the primary point of contact for the exchange of merchant shipping information between NATO's military authorities and the international shipping community. It also plays an important role in countering piracy.

The Standing Naval Force Atlantic, SNMG1's precursor, was activated in January 1968. The force was re-designated Standing NATO Maritime Group 1 in January 2005.

Standing Naval Force Mediterranean, SNMG2's precursor, was activated in 1992 in Italy. It deployed to the eastern Mediterranean Sea in support of Operation Active Endeavour, the precursor of Operation Sea Guardian. The force was re-designated Standing NATO Maritime Group 2 in January 2005.


The Standing NATO Mine Countermeasures Groups – SNMCMG1 and SNMCMG2 – are multinational forces composed of minehunters and minesweepers that primarily engage in search and explosive ordnance disposal operations. They also conduct historical ordnance disposal operations to minimise the threat from mines dating back to the World Wars, thereby contributing to global navigation safety. Both SNMCMG groups are key assets in the NATO Response Force (NRF) and are able to fulfil a wide range of roles.

SNMCMG1 was formed in the Belgian port of Ostend on 11 May 1973 to ensure safety of navigation around the ports of the English Channel and northwest Europe. Originally called "Standing Naval Force Channel", its name was changed several times to reflect its expanding area of operation.

SNMCMG2 developed from an on-call force for the Mediterranean, which was created in 1969. It also evolved over time to reflect its new responsibilities.

SNMCMG2 and SNMCMG1 were both given their current names in 2006.


Critical Undersea Infrastructure

Undersea cables carry an estimated USD 10 trillion in transfers every day; two thirds of the world's oil and gas is either extracted at sea or transported by sea; and around 95 per cent of global data flows are transmitted through undersea cables. For NATO, the protection of critical undersea infrastructure is essential to security and defence because it is key to securing and protecting the prosperity of Allied societies.

NATO has been working to enhance the security of critical infrastructure for years. Following the sabotage of the Nord Stream pipeline in September 2022, Allies have stepped up their military presence in the region. NATO has also created a Critical Undersea Infrastructure Coordination Cell to support engagement between NATO Allies, partners, and the private sector. NATO leaders agreed to establish a new NATO Maritime Centre for the Security of Critical Undersea Infrastructure within the Alliance’s Maritime Command in the United Kingdom. They also agreed to set up a network for NATO, individual Allies, the private sector, and other relevant actors to improve information sharing and exchange best practice.
In addition, NATO is working more broadly with the European Union through the NATO-EU Task Force on the Resilience of Critical Infrastructure, which includes critical undersea infrastructure in its work.


NATO's maritime operations and activities

Building on the strength of its naval forces, NATO's maritime operations have demonstrated the Alliance's ability to achieve strategic objectives in vastly different contexts.

Operation Sea Guardian

Operation Sea Guardian (OSG) maintains a safe and secure maritime environment in the Mediterranean Sea through three main tasks: maritime security capacity-building, situational awareness and counter-terrorism. The Operation was launched in November 2016 as the successor of Operation Active Endeavour.   

Allies and partners can flexibly contribute to Operation Sea Guardian in different ways: through "direct support" by placing assets under NATO operational command, and "associated support" with assets that remain under national command. Operation Sea Guardian is under the operational command of Allied Maritime Command in Northwood, United Kingdom, which serves as the Alliance's hub for maritime security information sharing.

Every year, Operation Sea Guardian conducts five to six focused operations in specific areas of interest in the Mediterranean. These operations use sea, air, sub-sea and other assets to gather, develop and maintain an accurate picture of daily activity in different parts of the Mediterranean Sea. In this context, most focused operations conducted under Operation Sea Guardian also includes port visits to non-NATO countries.

As part of Operation Sea Guardian, NATO cooperates with partner countries and other international organisations. For example, Australia contributed to Operation Sea Guardian in 2022 with a maritime patrol aircraft flight.

Support to the refugee and migrant crisis in the Aegean Sea

NATO has contributed to international efforts to assist with the refugee and migrant crisis since February 2016. To that end, as part of the Alliance's Aegean Activity, NATO ships have been conducting reconnaissance, monitoring and surveillance of crossings within the Aegean, in cooperation with the Greek and Turkish coastguards and through the establishment of direct links with Frontex (the EU's border management agency). NATO ships help to cut the lines of illegal trafficking within the Aegean Sea while providing maritime situational awareness.