NATO estimates that up to 40,000 Russian soldiers have been killed, wounded, captured, or missing in action in Ukraine.

• An alliance official confirmed to NBC News that NATO estimates that up to 40,000 Russian troops have been killed, injured, captured or gone missing during the first month of the Kremlin's war.
• According to an anonymous official source, between 7,000 and 15,000 Russian troops have died in the conflict.
• The Pentagon has previously refused to verify any reported estimates regarding the number of Russian troops withdrawn from combat.

An alliance official has confirmed to NBC News that NATO estimates that up to 40,000 Russian troops have been killed, injured, captured, or gone missing during the first month of the Kremlin's war in Ukraine.

According to NATO's latest intelligence assessment, between 7,000 and 15,000 Russian troops have died in the ongoing war, an official source has stated, requesting anonymity.

Russia's Ministry of Defense has the exclusive right to disclose the number of its troops who have died while fighting in Ukraine, as stated by Kremlin spokesman Dmitry Peskov on Tuesday.

Peskov stated that from the start, it was agreed that we lack the authority to disclose the figures during the special military operation, and he refused to provide additional details.

The Pentagon has previously refused to verify any reported figures regarding the number of Russian soldiers who have been killed or removed from the battlefield.

Since the US does not have troops on the ground in Ukraine, it is challenging for the Pentagon to provide casualty estimates, a senior US Defense official stated on a conference call on Wednesday.

The official stated that they would not specify the ranges we are examining because they are extremely broad and our confidence in these estimates remains low due to not being on-site to observe daily occurrences, as per U.S. intelligence reports.

As per the official statement, Russian forces are facing growing logistical, command and control, and morale problems.

Some Russian troops have been removed from the fight due to frostbite, according to an official. In another instance, an official stated that low morale among Russian soldiers led them to abandon their armored vehicles and walk away into the woods.

The U.S. intelligence community recently estimated that as many as 4,000 Russian soldiers have perished in the Kremlin's two-week conflict in Ukraine.

During an unclassified March 8 hearing with lawmakers, Lt. Gen. Scott Berrier, director of the Defense Intelligence Agency, shared that figure.

Berrier stated during the House Intelligence Committee's "Worldwide Threats" hearing that the number, between 2,000 and 4,000, was based on intelligence sources as well as open sources, but he expressed low confidence in it.

On Wednesday, Jens Stoltenberg, NATO Secretary-General, announced that the alliance would undergo a significant expansion of its military presence.

NATO is likely to increase its military presence in Eastern Europe by deploying four new battle groups in Bulgaria, Hungary, Romania, and Slovakia, as stated by Stoltenberg.

Stoltenberg stated during a news conference prior to the NATO leaders summit in Brussels that he anticipates leaders will enhance NATO's posture across all domains, with significant increases occurring in the eastern part of the alliance on land, in the air, and at sea.

On Wednesday, Julianne Smith, the U.S. Ambassador to NATO, revealed to a virtual audience hosted by the Atlantic Council that the possibility of permanently stationing U.S. and NATO troops is being considered.

Smith stated that NATO is currently reassessing its medium- and long-term force presence in its eastern flank territory, with the new deployments conveying a clear message to Moscow.

Smith stated that permanent stationing or persistent rotations could be potential solutions. At this juncture, the military commanders must provide specific proposals to the alliance, and then we must assess the security environment's requirements.