Missing submarine hints at Russia's chilling plan: 'Radioactive tsunami'

A Russian submarine carrying a deadly nuclear weapon system has gone missing from its Arctic base with fears escalating about Vladimir Putin's next move.

The Belgorod submarine, believed to be the biggest in the sea, has been operating out of its White Sea base since July, but with it no longer there, officials fear its "doomsday weapon" might soon be deployed.

It comes as Putin recently warned his use of nuclear weapons is "not a bluff".

NATO warned its members of the missing submarine saying Russia may plan to test Belgorod's "Poseidon" weapons system, according to multiple reports.

It is unclear exactly when the warning was sent, but Italian newspaper La Repubblica reported the news on Sunday.

"Poseidon" is a drone equipped with a nuclear bomb that Russia has claimed is capable of creating a "radioactive tsunami", Italian media reported.

• Putin's health 'dramatically deteriorating' amid 'escalation' of war

• Australia makes demand in rare high-level China meeting: 'END THE WAR'

• Shocking footage highlights major flaw in Putin's plan: 'Playtime's over'

The nuclear bomb can be detonated at a depth of one kilometre near out from the coast, according to FoxNews.

Russian state media had reportedly claimed the device can create an almost 500-metre wave that smashes into coastal cities and irradiates them.

The 182-metre submarine was reportedly delivered to the Russian Navy as part of Putin’s program that aims to develop and operate a series of a new class of "super weapons."

Rebekah Koffler, a strategic intelligence expert and author of "Putin’s Playbook," warned that Russia would only use the powerful weapon as a last resort, according to Fox News.

For example,"in the event that Russia and the U.S. are in a direct kinetic war and Russia is losing."

Ms Koffler said the device likely won't be operational for a number of years, but Putin may be testing it as a means to intimidate both Ukraine its NATO allies in the West, the publication reported.

Do you have a story tip? Email: newsroomau@yahoonews.com.

You can also follow us on Facebook, Instagram, TikTok and Twitter and download the Yahoo News app from the App Store or Google Play.