Lithuanian President Dalia Grybauskaite (C) views the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)

Lithuanian soldiers take part in the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)

US soldiers take part in the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)

Military vehicles are seen in the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)

Soldiers take part in the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)

Military vehicles are seen in the "Iron Sword 2014" military exercise in Pabrade, Lithuania, on Nov. 13, 2014. The multinational military exercise "Iron Sword 2014" was held in Lithuania from Nov. 2 to 13, gathering over 2500 military personnel from nine NATO member states. (Xinhua/Alfredas Pliadis)