On Wednesday, over tea and pastries with veterans of the war in Ukraine, President Vladimir Putin announced that Russia had tested a new weapon.
"There is nothing like it," the Russian leader said of "Poseidon" - a nuclear underwater drone capable of carrying a nuclear weapon, which can be launched as a torpedo and which a senior Russian deputy said could "take entire countries out of service".
When it was first presented in 2018, Russian media reported that "Poseidon" would be able to reach a speed of 200 km/h and move along a "constantly changing route", which would make it impossible to intercept.
Putin's statement came just days after the announcement that Moscow had conducted a test of its "unlimited range" nuclear cruise missile "Burevestnik".
"A unique product, unmatched in the world," Putin said of "Burevestnik", noting that the missile is so new that "we still have to establish what it is, what class of weapons it belongs to".