"If we were approached by large groups of drones (..), if we were to experience such an attack, I have no doubt (..) that it would not be a coincidence (..), it would be an attack on alliance territory," Grinkevich said at a press conference in Vilnius.

In that case, NATO defense plans would be activated and additional forces would be placed at the disposal of NATO Command Europe, Grinkevičius pointed out.

"I won't go into detail about what our strengths and weaknesses are in this regard, but in the event of an armed attack and the application of Article 5 [of the NATO Treaty] [on collective defense], a lot more would start to happen, and it would be a completely different game, as we would say in America," added the NATO Supreme Allied Commander Europe.