Six British diplomats have been expelled from Russia after being accused of “spying and sabotage”.
The country’s FSB security service said they worked in the “political department” of the British embassy in Moscow.
A Foreign Office spokesperson called the claims “completely baseless”.
Ukraine war latest: Putin threatens NATO with ‘war’ over long-range missiles
They said the diplomats’ had been expelled in August “following action taken by the UK government in response to Russian state-directed activity across Europe and in the UK”.
“We are unapologetic about protecting our national interests,” the spokesperson added.
The FSB claimed the Eastern Europe and Central Asia branch of the Foreign Office was now a “special service whose main task is to inflict a strategic defeat on our country”.
News of the expulsion comes as President Vladimir Putin warned against Ukraine getting approval to use Western-supplied long-range missiles against Russia.
He said it would “significantly change the very essence, the very nature of the conflict” and “mean that NATO countries, US, European countries are at war with Russia“.
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Putin: ‘It will mean the direct participation of NATO.’
British Prime Minister Sir Keir Starmer and US President Joe Biden will meet in Washington on Friday with a decision on approving the missiles believed to be imminent.
On the plane to the US, Sir Keir said Britain did not “seek any conflict with Russia”.
“Russia started this conflict. Russia illegally invaded Ukraine. Russia could end this conflict straight away,” he told reporters.
“Ukraine has the right to self-defence and we’ve obviously been absolutely fully supportive of Ukraine’s right to self-defence – we’re providing training capability, as you know,” said the prime minister
“But we don’t seek any conflict with Russia – that’s not our intention in the slightest.”
Kremlin ‘punishes’ UK – but timing of announcement is interesting
The very public expulsion by Russia of six British diplomats in Moscow, accused of involvement in spying and sabotage, is a way for the Kremlin to punish London.
Revoking the accreditation of diplomats is a tool that all countries can use to attack each other or send signals of anger.
The UK expelled almost two dozen Russia officials in London, accused of spying, in the wake of the novichok nerve agent poisoning of Sergei Skripal, the former Russian double agent, and his daughter Yulia in 2018.
This triggered a tit-for tat rejection of some British officials at the embassy in Moscow.
In the wake of Russia’s full-scale invasion of Ukraine, there have been further expulsions by the UK and – in much greater numbers – other European allies.
In May of this year, Britain announced it was expelling Russia’s defence attache, accusing him of being an “undeclared military intelligence officer” amid concerns about what the UK described as a campaign of “malign activity” by Moscow across the UK and Europe.
The Kremlin retaliated by expelling the British defence attache from Moscow.
The most recent expulsions of UK diplomats are thought to be linked to these escalating tensions as opposed to having anything to do with the UK support for Ukraine.
However, the timing of the publication of the decision by Russian state media on Friday is interesting.
It comes as the UK and the US are weighing up whether to allow Ukraine to use their long-range missiles to strike targets inside Russia – a move that President Putin has said would be regarded as Western allies directly joining the war against Russia.
Sir Keir Starmer and Joe Biden are due to meeting Washington on Friday with a decision of green-lighting the use of UK-French Storm Shadow cruise missiles thought to be imminent.
Ukraine’s President Volodymyr Zelenskyy has for months been asking permission to fire long-range Storm Shadow missiles, as well as US-made ATACMS missiles, into Russia to limit its ability to launch attacks.
The dial may now have shifted after the US accused Russia of taking delivery of ballistic missiles from Iran, against the warnings of the West.
US secretary of state Antony Blinken called it a “dramatic escalation”.
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Biden could allow Ukraine to hit Russia with US missiles
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President Biden has previously limited the distance US-provided missiles can be fired across the border amid concerns over an escalation.
Five weeks ago, Ukraine also launched an incursion into Russia’s western Kursk region in a bid to gain an advantage in the war and divert Russian troops from Ukraine’s Donetsk region.
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President Zelenskyy said on Thursday Russia had started a “counteroffensive action” in Kursk, but that Ukrainian forces had anticipated it and were ready to fight.
Russia’s defence ministry said 10 settlements had been recaptured.