Russian President Vladimir Putin has said the Russian navy will be armed with hypersonic nuclear weapons and underwater nuclear drones.
The weapons, some of which have yet to be deployed, include the Poseidon underwater nuclear drone, designed to be carried by submarines, and the Tsirkon (Zircon) hypersonic cruise missile, which can be deployed on surface ships.
The combination of speed, manoeuvrability, and altitude of hypersonic missiles, capable of travelling at more than five times the speed of sound, makes them difficult to track and intercept.
Putin, who said he does not want an arms race, has often spoken of a new generation of Russian nuclear weapons he says are unequalled and can hit almost anywhere in the world. Some Western experts have questioned how advanced they are.
Speaking on Sunday in St Petersburg at an annual naval parade that showcases Russia's best warships, nuclear submarines and naval aviation, Putin said the navy's capabilities were growing and it would get 40 new vessels this year.
He did not specify when it would receive new hypersonic weapons, but suggested that day was drawing closer.
"The widespread deployment of advanced digital technologies that have no equals in the world, including hypersonic strike systems and underwater drones, will give the fleet unique advantages and increased combat capabilities," Putin said.
In a separate statement released via Russian news agencies, the defence ministry said testing of the Belgorod, the first submarine capable of carrying the Poseidon drones, was under way and testing of the weapons systems was nearing completion.
"Work is being successfully completed to create modern weapons systems for the navy," it was cited as saying.
Putin last year threatened to deploy hypersonic missiles on ships and submarines that could lurk outside US territorial waters if the United States moved to deploy intermediate-range nuclear weapons in Europe.
Washington has not deployed such missiles in Europe, but Moscow is worried it might.