The scenario for the drills comprises a NATO military response to a range of potential challenges "from the effects of subversion and terrorist attacks to conventional warfare, cyber-attacks, Hybrid Warfare and humanitarian crisis," according to a bloc's news release.
"Exercise Trident Juncture will demonstrate that NATO is ready and able to defend any ally against any threat in any form," NATO Deputy Secretary General Alexander Vershbow said at the opening ceremony of the drills' live exercise, held on Monday.
Commander of NATO forces in Europe Philip Breedlove said the Trident Juncture drills send "a very clear message to any potential aggressor."
"We seek confrontation with no one. That is why we have invited observers from around the world," Vershbow stressed.
The first part of "Trident Juncture – 2015" — two-week-long command and staff drills that began on October 3 — wrapped up in Canada, Norway, Germany, Belgium and the Netherlands last Friday.