This footage appears to show a Russian frigate launching a salvo of cruise missiles from its position in the Black Sea towards military targets in Ukraine.

The video was released by the Ministry of Defence (MoD) of the Russian Federation on June 15.

The Russian MoD said: ‘The crew of the frigate of the Black Sea Fleet from the Black Sea carried out a salvo launch of four Caliber cruise missiles at the military infrastructure of the Armed Forces of Ukraine.'

The 3M-54 Kalibr (Caliber) is a family of Russian cruise missiles developed by the Novator Design Bureau. There are ship-launched, submarine-launched and air-launched versions of the missile, which entered service in 1994.

The Russian MoD did not specify if the missiles hit their intended targets or where in Ukraine they were located.

In its latest briefing, the Russian MoD said that from February 24 to June 15, ‘203 Ukrainian airplanes and 131 helicopters, 1,211 unmanned aerial vehicles, 339 anti-aircraft missile systems, 3,558 tanks and other armored combat vehicles, 524 multiple launch rocket systems, 1,958 field artillery and mortars, as well as 3,623 units of special military vehicles were destroyed during the operation'.

The General Staff of the Armed Forces of Ukraine reported that over the same period, Russia had lost 32,750 personnel, 1,440 tanks, 3,528 armoured fighting vehicles, 722 artillery systems, 230 multiple launch rocket systems, 97 anti-aircraft systems, 213 warplanes, 179 helicopters, 2,485 motor vehicles and fuel tankers, 13 warships, 591 unmanned aerial vehicles, 55 pieces of special equipment, and 129 cruise missiles.

In related news, the first civilian corridor out of the encircled city of Sievierodonetsk should, in theory, be open.

It is not clear if Russia has halted its attacks in the key eastern city to allow for evacuation, and hundreds of civilians are said to be trapped in a huge chemical plant.

The Russian army has said that evacuated civilians will be transported to separatist-controlled areas of Luhansk Oblast.

But sceptics are pointing out that previous humanitarian corridors attempted in Ukraine have struggled to stay open.

Russian forces now control most of Sievierodonetsk after a month of intense combat, according to UK military intelligence.

Meanwhile, NATO ministers are in Brussels for talks as Russia's military advances in the Donbas region prompt pleas from Ukrainian officials for more Western weapons.

Russia invaded Ukraine on February 24 in what the Kremlin is calling a ‘special military operation' to ‘liberate the Donbass'.