US officials are taking 'irresponsible' Vladimir Putin threat to use nuclear weapons seriously

US officials have said they're taking Vladimir Putin seriously over his threat to use nuclear weapons after the Russian leader claimed he wasn't bluffing.

Putin issued the threat as part of a speech where he announced he was ordering a partial mobilisation of reserve troops following a series of defeats in Russia's invasion of Ukraine.

That means people with previous experience in the military will be called into the war effort unless they are too old or medically unfit.

It's the first time Russia has mobilised for war since the Second World War, with the Russian president's decision meaning that around 300,000 more soldiers would be raised for the invasion of Ukraine.

During his speech he claimed Russia would have the right to use nuclear weapons after accusing western nations of engaging in 'nuclear blackmail' and boasting that he had 'lots of weapons to reply'.

Putin said Russia would use all means available to defend themselves against a 'threat to the territorial integrity of our country' and insisted he was 'not bluffing'.

Kremlin Pool / Alamy Stock Photo

US officials have responded to Putin's threats by branding Putin as 'irresponsible' but insisting they'd take his words seriously.

White House spokesman John Kirby told ABC's Good Morning America that the US 'always have to take this kind of rhetoric seriously', though said their current stance wouldn't be changed yet.

He said: "It's irresponsible rhetoric for a nuclear power to talk that way.

"But it's not atypical for how he's been talking the last seven months and we take it seriously. We're monitoring as best we can, their strategic posture, so that if we have to, we can alter ours."

"We've seen no indication that that's required right now."

Kirby said Putin's threats of using nuclear weapons were 'definitely a sign that he's struggling' as almost seven months on from the invasion Russian forces have been retreating in the face of a Ukrainian counter-offensive.

MediaPunch Inc / Alamy Stock Photo

Putin's claims of using any means possible, including nuclear weapons, to defend the 'territorial integrity' of Russia may also extend to Ukrainian regions that his troops have occupied.

In the next few days a series of referendums on joining Russia are due to be held in the Ukrainian regions of Donetsk, Luhansk, Kherson and Zaporizhzhia which are currently occupied by Putin's troops.

If those votes go the way Putin is clearly intending them to and they are split off from Ukraine in Russian eyes then he could soon be counting them as parts of Russian territory.

That could mean that if Ukraine tries to take back all the territory the Russians have seized during their invasion he would see it as a reason to go nuclear.

UK defence secretary Ben Wallace has already responded to Putin's threats of using nuclear weapons and decision to mobilise more troops, saying they are 'an admission that his invasion is failing'.

He said Putin's regime had 'sent tens of thousands of their own citizens to their deaths' and accused Russia of becoming a 'global pariah'.

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