A Western official said: “They seem to be trying to expand the pool in all sorts of different ways and avoid a widespread call to arms.
“They are not sure that Muscovites and those from St. Petersburg, Yekaterinburg and elsewhere will be willing to do that.”
Officials said the West isn’t expecting the worst from either the russian economic blow to arrive until the fall when sanctions, such as oil embargoes, begin to bite.
There has been massive speculation about mass mobilization since the start of the war, but Putin has resisted the urge to send civilians into battle, even as the Russian military struggles to gain ground.
British intelligence last month estimated that 55 percent of Russian-backed separatist forces in Donetsk were lost, calling the casualties in the Donbas “extraordinary”.
Morale in the Russian army is said to be low and new recruits reportedly receive only three to seven days of training before being sent into battle.
The defense ministry said on Monday that exhaustion will also hurt the advance of the Russian army.
It said: “The lack of planned interruptions to intense combat conditions is most likely one of the most damaging of the many personnel issues that the Russian Defense Ministry is struggling to rectify among the deployed forces.”
The Kremlin had expected to take control of key cities in Ukraine within days, but Russia faced fierce opposition from the Ukrainian army, which was supported by equipment and money from the West.
A series of military setbacks has forced the Kremlin to refocus its efforts in eastern Ukraine, but progress has been slow despite the capture of the city of Luhansk.