Russian forces have started military drills near Ukraine simulating the use of tactical nuclear weapons in response to what Moscow deems threats from western officials about increased involvement in the conflict.
Vladimir Putin ordered the drills earlier this month in a move Russian officials said was a warning to the west not to escalate tensions further.
The Kremlin has particularly been angered by the French president, Emmanuel Macron, who floated the possibility of sending European troops to fight Russia in Ukraine, and by remarks from the UK foreign secretary, David Cameron, who said Ukraine had the right to use weapons supplied by London to target sites in Russia.
The Russian defence ministry published footage on Tuesday showing trucks carrying missiles to a field where launch systems had been prepared and troops at an airfield readying a bomber to carry a nuclear warhead.
The ministry said it was the first stage of the drills, which involved practising the loading of launch vehicles, driving to launch sites and loading planes with hypersonic Kinzhal missiles.
Russia has numerous weapons systems capable of delivering tactical nuclear warheads, meaning those designed for battlefield use, as opposed to strategic warheads that could wipe out whole cities.
Unlike strategic weapons, which have been subject to arms control agreements between Russia and the US, tactical weaponshave never been limited by any such pacts, and Russia has not released their number or any other details about them.
Also on Tuesday, a Russian general fired last year after complaining about problems his troops faced in Ukraine was arrested on bribery charges.
Maj Gen Ivan Popov, who commanded the 58th Combined Arms force, which is fighting on the frontline near Zaporizhzhia, said last summer that he had been fired after he brought up problems on the battlefield, including the lack of counter-battery fire, and deaths and injuries the army was suffering from Ukrainian attacks.
Putin removed his longtime ally Shoigu from his role as defence minister earlier this month. Two other senior defence officials have also been arrested on corruption charges.
