The flagship of Russia's Black Sea fleet has sunk after being heavily damaged after Ukrainian officials claimed to strike the ship with two missiles.

The governor of the Odesa region claimed they struck the vessel with  Neptune anti-ship missiles, however Russia did not acknowledge any attack on the Moskva. 

Russia's defence ministry confirmed the ship had sunk while being towed to a port after previously stating a fire broke out on the cruiser leading to an ammunition explosion.

The vessel's crew, which was typically around 500-strong, was evacuated after the blaze spread.

It had previously said the blaze had been contained and that the ship would be towed to port with its missile launchers intact.

Officials in Moscow abstained from stating that the vessel was hit by Ukraine forces. 

It is also a blow to Russian prestige in a war already widely seen as a historic blunder.

Now entering its eighth week, Russia’s invasion has stalled because of resistance from Ukrainian fighters bolstered by weapons and other aid sent by Western nations.

The news of the flagship’s damage overshadowed Russian claims of advances in the southern port city of Mariupol, where they have been battling the Ukrainians since the early days of the invasion in some of the heaviest fighting of the war — at a horrific cost to civilians.

Russian Defence Ministry spokesman Maj Gen Igor Konashenkov said that 1,026 Ukrainian troops surrendered at a metals factory in the city.

Meanwhile, the UK Ministry of Defence, warned that the humanitarian situation is worsening. 

An intelligence update added: "Heavy fighting and Russian airstrikes have continued in the encircled city of Mariupol.

"The humanitarian situation in the city is worsening.

"Most of the 160,000 remaining residents have no light, communication, medicine, heat or water. Russian forces have prevented humanitarian access, likely to pressure defenders to surrender."