One military expert believes Russian President Vladimir Putin is running out of steam in his war against Ukraine and said Russian forces are quickly losing morale.

In a little over a month, Russia has lost an estimated 7,000 to 15,000 troops, according to a senior NATO official. As of March 17, Russian forces have lost over 230 of their heavily armored tracked vehicles, according to the Wall Street Journal. 

Ukraine's government believes the amount of equipment lost by Russian forces is much higher and estimates that more than 400 Russian tanks have been destroyed, according to the report.

The United States and other NATO allies have given billions of dollars in military aid and humanitarian assistance to Ukraine, which has the potential to increase Russia's losses.

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Putin

Russian President Vladimir Putin attends a meeting of the Supreme Eurasian Economic Council in Yerevan, Armenia. (Shutterstock)

Michael Ryan, former deputy assistant secretary of defense for European and NATO Policy told Fox News Digital that Russian forces may have run out of momentum and have reached a "culminating point."

He says a culminating point is when an army runs out of supplies, saying "it just reaches the limit."

"Most military observers and very senior American army generals believe that the Russian army reached a culminating point. A significant aspect of that is the losses that they've sustained," Ryan said.

Ryan says that, at conservative estimates, Russia has lost 10% of its overall force in Ukraine, while some estimates suggest a much higher amount, which he argues has a significant effect on Russian troop morale.

"In any event, [Russian losses are] significant from the standpoint of their ability to achieve their aims," Ryan said. "It also has a significant impact on morale, and I think the Russian military started with very low morale at this operation."

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NLAW anti-tank Ukraine weapon

Ukrainian soldiers take part in an exercise for the use of NLAW anti-tank missiles at the Yavoriv military training ground close to Lviv, western Ukraine, Jan. 28, 2022. ( AP Photo/Pavlo Palamarchuk, File)

He said that the "biggest challenge" for the Russian military, based on its losses so far, is morale of the troops.

"They were out in the field for a very long time. It seems most of them didn't know they were going to war. And they certainly didn't expect to be going into that type of battle that they've gone into. They weren't well prepared for it. They're not executing well, and they're not well supplied," Ryan said.

Ryan added that a good amount of Russian soldiers have family and friends in Ukraine, which made it hard for troops to make sense of being given orders to invade the country.

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Ukraine's biggest national flag flies in Kyiv

Ukraine's biggest national flag flies in Kyiv Feb. 26, 2022.  (Genya Savilov/AFP via Getty Images)

Perhaps one difference maker has been the way Ukraine goes about attacking Russian forces, according to Ryan.

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"Ukrainians are being very, very savvy about how they attack the Russian army," Ryan said. "The vehicles they've destroyed and the people that they've killed. You see the number of colonels killed, it has been significant. They're really creating chaos and confusion inside the Russian army, which means the numbers are even more important than they seem because of the specific targets the Ukrainians have been selecting."