Vladimir Putin has pulled his ambassador from London just days after Russia's grim threat of "consequences" to Britain.
In what appears to be an effort to pressure the UK into rethinking its support for Ukraine, Andrey Kelin left his post last month after more than seven years as Moscow's envoy to the UK.
No candidate has yet been put forward to take his place - while embassy staff have no idea when a successor might be named, according to The Times.
The absence of a replacement has raised alarm that diplomatic relations between the two nations might be circling the drain.
There are growing fears of a total collapse in communication between the Russian and British governments.
Tensions escalated further last week when it was revealed that British-manufactured drones had been deployed by Ukraine to strike targets inside Russia, with Mr Putin's London embassy warning of unspecified "consequences".
Kremlin propagandists then raised the threat level even higher, warning of a submarine-launched nuclear strike on the UK.
A Russian embassy spokesman accused Britain of pursuing a "path of confrontation" with Moscow.
He said Mr Kelin had made "considerable efforts to preserve contacts and channels of communication" with the UK as he fled back home.
"He left Britain in the hope that a more constructive and respectful dialogue could eventually be restored, should the UK reconsider its policies towards our country," the spokesman said.
Mr Kelin's exit was first revealed internally on June 11 at an embassy gathering for Russia Day.
That same day in Moscow, Britain's ambassador Nigel Casey joined French and German counterparts for unusual discussions with Russia's Deputy Foreign Minister, condemning the Kremlin's aggression in Ukraine.
And the spokesman further confirmed that the Kremlin has not yet put forward his replacement, with the charge d'affaires leading the operation in the meantime.
READ MORE ON RUSSIA:
- Double-tap drone strike on Ukrainian mall leaves 15 dead in Volodymyr Zelensky’s hometown
- Russian nursery children held at gunpoint under Vladimir Putin's orders
- 'Putin's palace' left unprotected after Ukraine wipes out ALL its air defences
Whether Moscow plans to leave a lower-ranking diplomat in charge indefinitely remains unclear.
The delay may signal that Russia thinks Britain doesn't deserve top-level political representation.
Since Moscow's threats last week regarding British-made drones being used for deep strikes inside Russia - including warnings from Foreign Minister Sergey Lavrov - no back-channel military contact has taken place, a defence source told The Times.
While a senior diplomatic source said the breakdown in dialogue was deeply concerning.
"It's important to maintain those channels of communication, especially between hostile states.
"Communication and de-escalation is the only tool to avoid potentially dangerous scenarios from turning catastrophic," the source said.
A national security source cautioned that the withdrawal could be a calculated message from the Kremlin, driven by anger over Britain's prominent role in arming Ukraine.
"They are basically saying: 'You guys don't matter,' and that, frankly, London and the UK don't count for anything any more," the source said.
Withdrawing an ambassador is a recognised method for a state to register serious displeasure without fully severing ties.
A relationship can also be quietly downgraded simply by failing to nominate a successor.
Our Standards: The GB News Editorial Charter
