An attack on Vladimir Putin's Moscow hub is “bound to happen,” according to a top Kremlin official.

Russia's former deputy foreign minister, Andrei Fedorov has outlined what he believes to be an inevitable threat that will cross one of of Putin's “red lines”.

Speaking candidly on Russian state TV, Putin's former adviser spoke about what would cause Putin to turn his invasion of Ukraine into a full scale world war.

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He replied: "It's a strike on the command centres in Moscow. A strike, not an attempt.

“The strike that's bound to happen, it's going to be a red line.”

An attack on Moscow is a "red line" for Putin
An attack on Moscow is a 'red line' for Putin

And he later said that Ukraine might start retaliating directly onto Russia by bombing Russian cities.

Since the invasion began almost exactly one year ago, Ukraine has been fighting in mainly defensive position – which has appeared to be better than Russia's attack in most cases.

But now the strange admissions for Ukraine taking the front foot are slowly starting to creep through on Kremlin-backed television, which has never been allowed before.

Fedorov added: “They'll be striking them (Russian cities) to a larger extent.

“(When asked about Moscow) Yes, Moscow.”

Ukraine "could declare war" on Russia
Ukraine 'could declare war' on Russia

Putin might find it difficult to protect his key cities, however, after it was revealed that he had lost more than 50% of his airborne forces in Ukraine.

The Kremlin has never released full figures about losses suffered since starting its invasion into Ukraine nearly 12 months ago.

However, Ukraine has claimed that more than 120k troops have been killed, with more than 400k more suffering injuries so severe that they can no longer fight.

Andrei Fedorov issued the warnings on Russian state TV
Andrei Fedorov issued the warnings on Russian state TV

Mikhail Zvinchuk, a former military press official, told Russian state TV that the air division of Putin's army has suffered huge losses.

He said: “Many are saying that you can’t see the airborne troops on the frontline.

“Unfortunately, this is the objective reality – by the start of mobilisation, our airborne forces lost 40-50% of staff.

“As of now, out of the old and tested formations with designated equipment, not that many are remaining.”

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