They stressed that the Russian president had had to turn to “disparate personnel“ after Russian forces suffered heavy losses, with at least 15,000 of his troops believed to have been killed, with three to four times as many wounded or incapacitated.
These casualties had left Russian generals with “significant resourcing problems” in Ukraine.
In its latest intelligence update, the Ministry of Defence said in London: “Despite Russian forces having encircled Mariupol for over ten weeks, staunch Ukrainian resistance delayed Russia’s ability to gain full control over the city.
“This frustrated its early attempts to capture a key city and inflicted costly personnel losses amongst Russian forces.”
It added:”In attempting to overcome Ukrainian resistance, Russia has made significant use of auxiliary personnel. This includes a deployment of Chechen forces, likely consisting of several thousand fighters primarily concentrated in the Mariupol and Luhansk sectors.
“These forces likely consist of both individual volunteers and National Guard units, which are routinely dedicated to securing the rule of Chechen Republic Head, Ramazan Kadyrov.”
The briefing continued: “Kadyrov likely maintains close personal oversight of the deployment, while his cousin Adam Delimkhanov has likely acted as the Chechen field commander in Mariupol.
“The combat deployment of such disparate personnel demonstrates Russia’s significant resourcing problems in Ukraine and is likely contributing to a disunited command which continues to hamper Russia’s operations.”
More than 200 Ukrainian soldiers, many of them wounded, have been bussed out of the sprawling Azovstal steelworks in the besieged southern port of Mariupol.
Ukraine’s president Volodymyr Zelensky has said it will take time to agree the withdrawal of more of his forces in their last redoubt in the steel mill in the city.
These talks may be thwarted by moves in Moscow to treat these Ukrainian soldiers as “terrorists” which has raised fears that they will be executed in another appalling war crime by Mr Putin’s regime.