Vladimir Putin is preparing to send thousands of inexperienced new conscripts to fight in Ukraine as his invasion continues to stall, Western officials believe.
Russia has signed some 130,000 new conscripts into its army.
The number is "unusually high" leading intelligence chiefs to believe some will be sent to the war in Ukraine.
It comes as the Russian president is redeploying his forces in Georgia to bolster his invasion.
"According to our defence intelligence, Russia is redeploying elements of forces in Georgia to reinforce the invasion of Ukraine," a western official said on Monday.
"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 has said only professional soldiers will go to Ukraine."
The Ukrainian president spoke to locals about the horrors inflicted on their community and vowed Putin and soldiers who brought such “evil to our land” would be punished for war crimes.
Britain condemned the “whole new world of horror” unleashed by Putin and vowed to lead the global response to force him to end his barbaric invasion.
Western Officials said on Monday: “The commanders of those units will be indictable for war crimes, they will be individually and personally accountable, as will their generals.”
But they warned "to do a proper war crimes investigation that would stand up in a court of law you need judicial level investigators".
"That is obviously something for the future," they said.
"But I think the Ukrainians will do their best to preserve evidence, as will The Human Rights Council commission of inquiry.
“The British personnel involved in this are at the moment ready to help the International Criminal Court (ICC) investigation with their interpretation of images. There's no investigation itself being done by British military personnel, but their skills have been used in these situations before and they are ready to help the ICC investigators."
It comes as no "concrete" agreements were made at peace talks between Ukrainian and Russian delegations last week.
"I think there is still some doubt as to whether Putin is really interested in negotiations or even a ceasefire," the Western official said.
It is believed sanctions imposed by Britain and other nations have also had a significant impact on the Russian economy, with intelligence suggesting the country's economy is on course for "a deep recession" this year.
"In 2022. GDP growth forecasts range from minus 7 per cent to minus 12 per cent. That would mean it's worse than the 1998 financial crisis, which hit Russia but also worse than 2008 for them."
The intelligence chiefs added the UK has no plans to expel Russians from the London embassy over the Ukrainian invasion because few intelligence officers remain.
They said: "A number of European partners have expelled Russian diplomats, principally intelligence officers.
"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."