It was one of the most surprising moments of the Ukraine war so far and speculation continues about the circumstances surrounding the sinking of Russia's Moskva missile cruiser warship.
Observers have warned the embarrassing loss could push Putin to go nuclear, while some in the Kremlin-backed media are now banging the drum for "World War III".
A number of Ukrainian experts have raised the possibility that the 12,500-ton cruiser – a critical military asset for the Russians – could have been carrying nuclear weapons.
Mykhailo Samus, deputy director of the Lyiv-based Center for Army, Conversion and Disarmament Studies is among those to have raised the prospect.
Writing on Facebook, he said the warship could have been carrying two nuclear warheads when it was hit.
"They could have been unequipped and stored in a protected area, so most likely they were not damaged by ... explosion," he wrote.
However CNN reporter Jim Sciutto that US officials do not believe the ship was carrying nuclear weapons, citing two senior officials.
"US has been monitoring Russian forces for unusual movement of nuclear weapons and has not detected such movements to date," he tweeted.
In an interview due to air in the United State on Sunday night, Ukrainian president Volodymyr Zelensky told CNN that "all of the countries of the world" should be prepared for the possibility that Putin will use tactical nuclear weapons in this ongoing war.
"We should think not be afraid, not be afraid but be ready. But that is not a question for Ukraine, not only for Ukraine but for all the world, I think."
Ukraine says the Moskva's fate was sealed by a missile strike launched by its forces from the coast which ripped open the hulking Soviet-era ship's hull. Russia's defence ministry has not confirmed that version of events but admitted the ship was sunk.
Russian TV host says operation has 'escalated into World War III'
Russian state TV propagandists meanwhile have baselessly claimed World War III has ignited in the wake of the ship's sinking.
"One can safely call what it has escalated into World War III That’s absolutely for sure," TV presenter Olga Skabeyeva told her viewers, when discussing why Russia's invasion continues to drag on.
A clip of the moment was transcribed by Francis Scarr at BBC Monitoring, which keeps an eye on the activities of Russia's state media arms.
And here we have it - in a rant seemingly aimed at explaining to viewers why the "special operation in Ukraine" is taking so long, Russian state TV presenter Olga Skabeyeva says her country is fighting World War Three against Nato
I've added subtitles pic.twitter.com/MQW0UfiQso
— Francis Scarr (@francska1) April 14, 2022
What does the sinking of Moskva mean for Russia?
Russia has powerful air defence systems deployed in Crimea, which it seized from Ukraine in 2014, but the Moskva was able to provide long-range and mobile air defence protection for the entire Black Sea Fleet and was a floating command and control centre. Its loss degrades the fleet's air defences, particularly on longer range missions.
Can Russia replace its capabilities?
No. Russia has two other ships of the same class, the Marshal Ustinov and the Varyag, which serve with Russia's Northern and Pacific fleets respectively. Turkey, which controls access to the Black Sea via the Bosphorus, will not let them enter at a time of war.
What happened to the crew on board?
The ship had a crew of around 500 sailors who Russia said were successfully evacuated to other ships before being returned to their home port of Sevastopol in Crimea on Friday (local time). Ukraine has suggested there are likely to have been fatalities.
Will the loss of Moskva change the course of the war?
Unlikely to, but Britain's Ministry of Defence says its loss is likely to prompt Russia to review its naval posture in the Black Sea. US officials, speaking to Reuters on condition of anonymity, said that while the sinking would have a symbolic impact and potentially raise questions about Russia's longer-term naval capabilities, it would be unlikely to have a major impact on the course of the conflict. The Russian navy has so far not played a big role.
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