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 Deployments and operations


NATO's Maritime Operation in the Mediterranean
Operation Sea Guardian's patch


Operation Sea Guardian is a flexible operation that can potentially cover the full range of Maritime Security Operations (MSO) tasks. At present, it is carrying out maritime security capacity building, and providing support to maritime situational awareness and to maritime counter-terrorism.

Operation Sea Guardian can execute any of the four additional MSO tasks, if requested by the Noth Atlantic Council (NAC):

  • Uphold freedom of navigation.
  • Conduct maritime interdiction.
  • Fight the proliferation of weapons of mass destruction.
  • Protect critical infrastructure.

Through Operation Sea Guardian, NATO is contributing to the maintenance of a secure and safe maritime environment, while collaborating with other actors, such as the European Union (EU).

Background information

In today’s globalised economy, 90 per cent of the total volume of goods is moved by sea and communication cables that carry 95 per cent of the world’s cyberspace traffic lie on the sea-bed. The Mediterranean Sea is no exception. In terms of energy alone, some 65 per cent of the oil and natural gas consumed in Western Europe pass through the Mediterranean each year.

In this context, NATO launched Operation Sea Guardian in November 2016, which aims to reinforce maritime situational awareness, counter-terrorism efforts including through the hailing and the boarding of suspect vessels, and capacity-building in the Mediterranean Sea. These tasks focus on gathering relevant information about current maritime activities in the Mediterranean region to help identify possible security concerns, and therefore continue to develop maritime security awareness in the region. Nevertheless, if the NAC so decides, the Operation can conduct any of the agreed four additional MSO tasks: uphold freedom of navigation, conduct maritime interdiction, fight the proliferation of weapons of mass destruction, and protect critical infrastructure.

Within the framework of Operation Sea Guardian, NATO supports the EU’s Operation Sophia with regard to information-sharing, logistical support and the implementation of the United Nations Security Council Resolution 2357 (the arms embargo against Libya).

As such, the Mediterranean offers opportunities to deepen maritime cooperation at operational and tactical levels between NATO and the EU, building on previous experience and successes, in particular in the Indian Ocean and the Aegean Sea.

The Operation comes under the operational command of the Allied Maritime Command (MARCOM), Northwood, United Kingdom. MARCOM serves as the hub of maritime security information-sharing for the Alliance.

North Atlantic Council (NAC)


In July 2015, the North Atlantic Council (NAC) decided to modify the Operation Active Endeavour (OAE) to a non-Article 5 operation based on networks, instead of platforms (units) as OAE did.

After finishing Operation Active Endeavour, on 9th November 2016, Operation Sea Guardian (OSG) was activated.

The contours of sea guardian

Operation Sea Guardian succeeded Operation Active Endeavour. Similarly to the latter, Operation Sea Guardian operates in the Mediterranean and performs the three below-mentioned MSO tasks. However, it is a non-Article 5 operation as Operation Active Endeavour was.

  • Support maritime situational awareness: the focus is on information-sharing between Allies and with civilian agencies to enhance the NATO Recognised Maritime Picture (RMP).
  • Support maritime counter-terrorism: this involves the planning and conduct of a range of operations to deter, disrupt, defend and protect against maritime-based terrorist activities. Essentially, these operations aim to deny terrorists access to designated areas and contain threats through the use of forcé.
  • Contribute to maritime security capacity building: NATO aims to contribute to the international community’s efforts in developing maritime security with both military and non-military authorities. 

If agreed by the NAC, Operation Sea Guardian can perform the following four additional MSO tasks:

  1. Uphold freedom of navigation: NATO must be ready and able to act in compliance with and support the principle of freedom of navigation in times of peace and war. This includes surveillance, patrol, maritime interdiction, Special Operations, deployment of law enforcement detachments and, when authorised, the use of force.
  2. Conduct maritime interdiction: assets can be assigned for quick-response actions and may use Special Operations Forces and experts in chemical, biological, radiological and nuclear (CBRN) weapons to board suspect vessels.
  3. Fight the proliferation of weapons of mass destruction: the aim is to prevent the transport and deployment of weapons of mass destruction, and involves the ability to locate, identify and secure illicit CBRN material transiting at sea.
  4. Protect critical infrastructure: at the request of a NATO or non-NATO country and in accordance with directions from the NAC, NATO helps protect critical infrastructure in the maritime environment, including the control of choke points.
Spanish involvement


With the approval of the Council of Ministers, Spain is contributing with the following units to Operation Sea Guardian:

  • An average of 4 departures per month of  Maritime Patrol Airplane (MPA)
  • One submarine in two periods of 45 days, one per semester
  • An offshore patrol boat ready to departure in 48 hours on request
  • A leading command ship with an onboard staff available on request
  • Permanent diplomatic authorization for Cartagena and Rota naval bases

Spain also offers support, on request, to those naval units in transit within Sea Guardian's area of operations.


  • February 7 to 16. Spanish Patrol vessel 'Meteoro' takes part on exercise FOCOPS 01/21. 
  • February 3rd. Frigate 'Cristóbal Colón', SNMG2's flagship, is sailing on associate support to Operation Sea Guardian.


  • December 10th. The submarine 'Tramontana' concludes its participation in OSG.
  • November 6th. Submarine 'Tramontana' joins NATO's  Operation Sea Guardian.


  • October 2nd. The submarine ‘Mistral’ has been integrated into the operation for 26 days in the fight against terrorism.
  • June 10th. The frigate “Reina Sofía” leads the Force Commander of the Operation Sea Guardian. It plans to remain integrated into this Operation till 30th June.
  • February 7th. Spanish submarine “Tramontana” is incorporated into the Operation “Sea Guardian”. This is the first deployment of this kind of unit planned for this year.


  • October 8th. The submarine “Tramontana” joins to the operation until April 2019.
  • April 23rd. The submarine “Mistral” ceases its participation in the operation.
  • March 12nd. The frigate “Navarra” ceases its command on the operation.
  • February 22nd. The submarine “Mistral” is incorporated into the Operation Sea Guardian.
  • February 14th. Spain leads the Operation Sea Guardian against terrorism in the Mediterranean Sea. Frigate Captain Francisco Javier Vázquez Sanz, Commander of the frigate “Navarra” (F-85) takes command of the group, which also includes the Italian frigate “Eolo” and the Belgian frigate “Louise-Marie”.


  • November 29th. The frigate “Numancia” ceases its participation in the operation.
  • October 23rd. The submarine “Tramontana” ceases its participation in OSG (Operation Sea Guardian).
  • August 23rd. The submarine “Tramontana” is integrated into the operation.
  • May-June. The patrol boat “Serviola” and the submarine “Galerna” are integrated into the OSG.


  • November 9th. The Operation Sea Guardian is activated.


  • Arrival of submarine 'Tramontana' in Cartagena

    Submarine 'Tramontana' docks in Cartagena after completing its deployment in NATO's Operation Sea Guardian

    Submarine 'Tramontana' docks in Cartagena after completing its deployment in NATO's Operation Sea Guardian


    Cartagena, Spain

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  • ‘Tramontana’ sails on surface

    Submarine ‘Tramontana’ stopover at Cagliari port

    Submarine ‘Tramontana’ stopover at Cagliari port


    Cagliari, Italy

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  • Deck preparation before set off

    Submarine ‘Tramontana’ joins NATO to counter terrorism

    Submarine ‘Tramontana’ joins NATO to counter terrorism



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  • “Mistral” submarine, 26 days of fighting against terrorism

    “Mistral” submarine, 26 days of fighting against terrorism

    “Mistral” submarine, 26 days of fighting against terrorism


    In Cartagena

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  • La ‘Reina Sofía’ ha contado con 222 militares

    La fragata ‘Reina Sofía’ finaliza su despliegue en la operación ‘Sea Guardian’

    La fragata ‘Reina Sofía’ finaliza su despliegue en la operación ‘Sea Guardian’


    En Rota

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