British intelligence has uncovered a plot by Russian President Vladimir Putin to install a pro-Moscow puppet leader in Ukraine, Foreign Secretary Liz Truss said in an extraordinary move.
In a highly unusual move, the Foreign Office levelled the accusation at Putin as he considers whether to mount an invasion against Russia's neighbour.
It took the unusual step of naming former Ukrainian MP Yevhen Murayev as a potential Kremlin candidate to take over the Ukrainian government in Kyiv in a Russian pupper regime.
British officials also named four former Ukrainian ministers suspected of colluding with Russian intelligence officers on a plan to attack Ukraine.
What do you make of the Foreign Office's move? Have your say in the comment section
The move comes as Western allies stepped up warnings that Russia will pay a heavy price if the estimated 100,000 troops massed on the border launch any kind of incursion into Ukraine.
And UK Prime Minister Boris Johnson warned his fellow European Union leaders against "naivety"over Putin’s Ukraine demands, as reported by the Telegraph.
In a statement, Foreign Secretary Liz Truss said the Russian plotting showed the lengths to which the Kremlin was prepared go to undermine the government in Kyiv.
"The information being released today shines a light on the extent of Russian activity designed to subvert Ukraine, and is an insight into Kremlin thinking," she said.
"Russia must de-escalate, end its campaigns of aggression and disinformation, and pursue a path of diplomacy.
"As the UK and our partners have said repeatedly, any Russian military incursion into Ukraine would be a massive strategic mistake with severe costs."
Mr Murayev, a media owner, lost his seat in the Ukrainian parliament when his party failed to secure 5% of the vote in elections in 2019.
He has reportedly spoken out in the past in support of Russia's annexation of Crimea from Ukraine in 2014.
In addition, the Foreign Office named four other Ukrainian politicians who, it said, maintained links with the Russian intelligence services.
It said some of them had been in contact with Russian intelligence officers working on the invasion plan.
They include Mykola Azarov who served as prime minister under the pro-Moscow president Viktor Yanukovych who was toppled in a popular uprising in 2014.
Mr Azarov fled to Russia where he established what was widely seen as a puppet government-in-exile.
He has been the subject of international sanctions and an Interpol "red notice" issued at the request of the Ukrainian government.
Also in the list is Vladimir Sivkovich, the former deputy head of the Ukrainian National Security and Defence Council, who was this week made the subject of US sanctions for allegedly working with Russian intelligence.
The others are Serhiy Arbuzov and Andriy Kluyev who both served as deputy prime minister under Mr Yanukovych.
Bois Johnson is said to consider the crisis as "gravely dangerous" and warned his European counterparts against "naivety" over the demanded conditions Putin has set on any Russian de-escalation of the situation, which include a ban on Ukraine joining Nato.
Germany's navy chief stepped down on Saturday after drawing criticism for saying Putin deserved respect and that Kyiv would never win back annexed Crimea from Moscow.
Vice Admiral Kay-Achim Schoenbach said Putin seeks to be treated as an equal by the West.
"What he (Putin) really wants is respect," Schoenbach said.
"And my God, giving someone respect is low cost, even no cost... It is easy to give him the respect he really demands - and probably also deserves."
Schoenbach added that "the Crimea peninsula is gone, it will never come back, this is a fact," contradicting the joint Western position that Moscow's annexation of the peninsula from Ukraine in 2014 cannot be accepted and must be reversed.
A Downing Street source told the Telegraph : “The Prime Minister’s view is that the situation in Ukraine is the biggest test to the unity and resolve of the West and the Nato alliance in decades.
“It would be frankly naive to assume that Russia could be mollified by changes to the European security architecture – the Kremlin’s behaviour has made that consistently clear.
“The UK is working through Nato and in lockstep with the US to enact a policy of dialogue and deterrence, pursuing the diplomatic track but readying a package of sanctions that will pierce the heart of Russia’s economy should that fail."
Britain has sent troops and defence weapons to Ukraine and on Saturday it was reported Russian defence minister Sergei Shoigu has accepted an invite to London to meet Defence Secretary Ben Wallace.
A senior defence source said: "The Defence Secretary is glad that Russia has accepted the invitation to talk with his counterpart.
"Given the last defence bilateral between our two countries took place in London in 2013, Russian defence minister Sergei Shoigu has offered to meet in Moscow instead.
"The Secretary of State has been clear that he will explore all avenues to achieve stability and a resolution to the Ukraine crisis. We are in communication with the Russian government."
More than 100,000 Russian troops, as well as equipment including tanks, were moved to the Ukrainian border this week.
This week President Joe Biden warned he believes an attack is ‘imminent’, although he was criticised for hinting any response would depend on the severity.
