In view of the terrorist attacks on the 11th of Sep. 2001, NATO, for the first time in its history, proceeded to activate Article V of the Foundation Agreement of the Alliance, thus considering them as armed attacks against an Alliance member state. The aim of NATO was to assist operations conducted by NATO naval forces, as part of the international antiterrorist campaign. In this context, the Standing Naval Force, Mediterranean and Atlantic, (STANAVFORMED and STANAVFORLAND) were tasked with the following missions in the East Mediterranean:
- Naval Presence, Observations and Surveillance Operations
- Protection of High Value Units
- Control of Sea Lines of Communication
- Maritime Inspection Operations
- Maritime Counter-Terrorism Operations
On the 4th of February 2003, NAC decided to expand the mission of «ACTIVE ENDEAVOUR» and include the escorting of the Alliance Merchant Ships sailing through the Gibraltar straight.
To render the operation sustainable, NATO has agreed with various states, such as Russia and the Ukraine, to allocate Units to the operation.
Since the 1st of October 2004, the operation has covered the whole Mediterranean and a new OPLAN was issued. The participating forces in the operation have been determined.