Lithuania has declared a state of emergency this December 9, due to the continuous flying of balloons from Belarus, Russia's closest ally. The balloons, which are used to smuggle cigarettes, have forced airport closures in recent weeks, stranding thousands of passengers. According to the Lithuanian government, they are a form of hybrid warfare and pose a "national security concern," as declared by Interior Minister Vladislavas Kondratovičius. European Commission President Ursula von der Leyen also called the recurring attacks in recent weeks "completely unacceptable."
Lithuania had closed its borders with Belarus for several weeks at the end of October because of the balloon threats.
Once a more cooperative partnership, ties between the North Atlantic Treaty Organization and Moscow have deteriorated sharply, today resembling the tense standoff of the Cold War. NATO leaders view Russia as a direct security threat, but repeated warnings and condemnations from the Alliance have so far had little effect on the Kremlin.
So, how has a previously constructive relationship between NATO and Russia turned so fractious? Click through this gallery and find out more about why Russia fell out with NATO.