
The refusal of Ukraine and NATO powers to recognise Moscow's authority over Crimea represents a "systemic threat" for Russia, former Russian president Dmitry Medvedev said on Sunday.
Russia annexed the Black Sea peninsula of Crimea from Ukraine in 2014 after a pro-Moscow president in Kyiv was toppled amid mass street protests. Moscow then also backed pro-Russian armed separatists in the Donbas region of eastern Ukraine.