Boris Johnson has said he fears Vladimir Putin may deploy chemical weapons in Ukraine as that would be “straight out of Russia’s playbook”.

Speaking on Sky News’ Beth Rigby Interviews programme, the prime minister said the only way the war in Ukraine can end is if the Russian president realises he has made a “catastrophic mistake”.

Putin could use chemical weapons

Mr Johnson reiterated Western officials’ fears that Mr Putin could use chemical weapons in Ukraine after Moscow accused Kyiv of planning to deploy them in the battlefield.

“The stuff that you’re hearing about chemical weapons is straight out of their playbook,” he said.

“They start saying that there are chemical weapons that have been stored by their opponents or by the Americans.

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“And so when they themselves deploy chemical weapons, as I fear they may, they have a sort of maskirovka – a fake story – ready to go.

“You’ve seen it in Syria. You saw it even in the UK. That’s what they’re already doing. It is a cynical, barbaric government.”

On Wednesday, Moscow said it had uncovered a military biological weapons programme in Ukraine involving deadly pathogens such as plague and anthrax and called on the US to explain the “Ukrainian biological weapons lab”.

A US official dismissed the claim as “absurd propaganda” and accused Russia of seeking retroactive pretexts for the war.

Reacting to Mr Johnson saying Russia could use chemical weapons, former British intelligence officer Christopher Steele told Sky News: “I certainly think if you look at what’s happened in Syria and Chechnya, and of course what happened on our own streets in Salisbury, I wouldn’t rule it out at all.

“And I think that as the Russian army becomes more bogged down and clearly not realising its objectives militarily you are likely to see more indiscriminate killing and bombardment and possibly the use of a chemical weapon.”

Key developments:
• Diplomatic talks in Turkey between Ukraine and Russia end without agreement
• Russia could use chemical or biological weapons in Ukraine, US warns
• Roman Abramovich sanctioned by UK government amid crackdown on Russian oligarchs
• British troops must not go to Ukraine to fight and ‘take some selfies’, Armed Forces minister warns
• Fleeing Ukrainian refugees can apply for digital visas to come to the UK

Former chief of UK defence intelligence Air Marshall Philip Osborne told Sky News the PM may have been warning about a chemical weapons attack because he has “really high-grade intelligence”.

“What is more likely is this is part of information warfare so Boris Johnson is trying to pre-empt or respond to information Putin is going to use chemical weapons,” he said.

“So he could go really hard on the rhetoric, structured around Russian misinformation about chemical weapons facilities being in Ukraine.

“It’s more likely this is a narrative/counter-narrative escalation.”

He added that Russia’s accusation Ukraine has chemical weapons could either be a narrative to “pre-empt” their use in Ukraine by the Kremlin or an excuse for why the invasion happened in the first place.

“The challenge is knowing which one – and that’s part of what the West now has to grapple with, and what does it mean for Ukraine and the rest of the world,” he said.

He added that if Russia did use chemical weapons it would be a “significant escalation and would be disproportionate to anything we’ve seen”.

However, he said: “We can never know what Putin’s thinking, you know what he’s saying and doing, but not what he’s thinking. It’s really dangerous to be really definite.”

Only Putin can accept he has made a ‘catastrophic mistake’

On whether there is a compromise to make Russia halt the invasion, the PM said it “depends on Putin and it’s up to him and to him alone”.

“I think he needs to understand that he’s made a disastrous miscalculation and that everybody can see that things aren’t progressing in the way that he hoped,” he added.

“His best bet, I think, is to withdraw, to cease the violence and to allow a peaceful negotiation to begin.”

He added that Mr Putin could either choose to accept he has made a “catastrophic mistake now…or a bit later on” but it is “up to the Kremlin”.

Mr Johnson warned the Russian president “needs to understand that his options are not good” but Mr Putin himself has “made it very difficult to find an offer”.

:: Watch Beth Rigby Interviews… on Sky News – on TV, online and the app – at 9pm tonight

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