Russia is ramping up its war effort in eastern Ukraine, and a senior U.S. defense official told reporters Friday that Moscow could look to recruit as many as 60,000 soldiers to join the fight

The official said the Pentagon has seen "indications" that Russia is looking to launch a "mobilization phase" as it refits soldiers in Russia and Belarus.

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Vitaly, 52, says he is of Russian origin and fought in the Russian army during the first Chechen war but fights alongside Ukrainian soldiers Feb. 9, 2022, in Pisky, Ukraine.  (Gaelle Girbes/Getty Images)


Moscow said last week that, in a show of good faith, it would remove troops from areas around the capital city of Kyiv and the northern city of Chernihiv. 

The U.S. and NATO have warned this is not a withdrawal, but a tactic to allow Russia to resupply its depleted troops and focus a "major offensive" in the eastern Donbas region.

But the senior U.S. defense official also noted that there have not been any "indications that there are fresh reinforcements."

The official said the U.S. is not seeing strong evidence that the soldiers who could be recruited to replenish the Russian troops will be "fully trained, fully armed" or even "fully ready" to enter the war. 

It is unclear how many Russian troops have been killed since the onslaught of the war more than six weeks ago, but Russian spokesman Dmitry Peskov said in an interview Thursday with Sky News that Moscow has seen "significant losses of [its] troops." 

Peskov did not provide a figure on the number of Russian causalities, but the Kremlin put the number close to 1,350 deaths in late March. 

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A dog is seen in the middle of a street as Ukrainian army soldiers take part in a military sweep to search for possible remnants of Russian troops after their withdrawal from villages in the outskirts of Kyiv, Ukraine, April 1, 2022.  (AP Photo/Rodrigo Abd)


A NATO official said that the figure was likely closer to between 7,000 and 15,000 deaths. The Ukrainian Armed Forces said this week that Russian troop causalities were more than 18,000, though these figures have not been verified. 

Despite apparent heavy losses over a matter of weeks, the senior U.S. official said Russia is believed to have maintained 80-85% of its fighting force from the start of the war. 

"We believe that they have not solved all of their logistics and sustainment problems," the official told reporters, noting that those logistic problems exist both within and beyond Ukraine’s borders. "So our sense is that they will likely not be able to reinforce the eastern part of the country with any great speed." 

But the senior defense official also noted that U.S. authorities expect the Russian offensive in eastern Ukraine to be a brutal fight. 

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A Ukrainian serviceman guards his position in Mariupol, Ukraine, March 12, 2022.  (AP Photo/Mstyslav Chernov)


 "This will be a knife fight. This could be very bloody and very ugly," the official warned. "The Russians are limiting their geographic aims, and they still have a lot of combat power available to them."

U.S. and NATO security officials have warned the war in Ukraine could continue for months, if not years to come.