Vladimir Putin could be forced to send conscripts to fight in Ukraine to make up for the huge losses Russia has already suffered, western officials believe.
Military intelligence also suggests the Kremlin is redeploying some forces in neighbouring Georgia to bolster its invasion.
The unexpected moves are seen as a further sign that the war is going badly wrong for Moscow thanks to the ferocity with which the Ukrainians are defending their country.
Around 130,000 conscripts are being called up by Moscow as part of the regular biannual spring draft.
But a western official said that was “an unusually high number”, suggesting they were destined for the frontline in Ukraine.
“According to our defence intelligence, Russia is redeploying elements of forces in Georgia to reinforce the invasion of Ukraine,” the official said.
“We don’t think this was planned, it’s a very odd thing for the Russian military to do so we expect it’s indicative of the problems they’re having in Ukraine.
“They’ve done the biannual draft but Putin has signed over 130,000 new conscripts into the army. The timing aligns with previous spring drafts but we think that’s an unusually high number.
“We do think there is a realistic possibility these conscripts will be sent to Ukraine, even though the Russian MoD [ministry of defence] have said only professional soldiers will go to Ukraine.”
Meanwhile, the official also said there were “no plans” to kick Moscow diplomats out of London, despite the fact that the Russian Embassy in London’s Twitter account continues to pump out Kremlin propaganda.
The official said few intelligence officers remain in the UK after so many were expelled following the Salisbury poison attack.
“A number of European partners have expelled Russian diplomats, principally intelligence officers,” the official said.
“Because of all the action we took after Salisbury we actually don’t have very many of that category of Russian in the embassy in London at the moment. So while we keep it under review we have no plans at the moment.”
Meanwhile, the Russian economy could shrink by 12 per cent this year as economic sanctions introduced following the invasion of Ukraine take effect.
The western official said: “Russia is on course for a deep recession in 2022 and it’s GDP could shrink by between 7 per cent and 12 per cent.
“That would mean it’s worse than the 1998 financial crash which hit Russia, but also worse than [the global financial crash in] 2008.”