Russia has reportedly been forming a strategic reserve from new recruits since July 2025. A Russian insider source that has consistently provided accurate reports about changes in the Russian military command stated on September 21 that roughly 292,000 people signed contracts with the Russian Ministry of Defense (MoD) between the start of 2025 and September 15—an average of approximately 7,900 recruits per week or 31,600 per month.[1] The insider source stated that some of these recruits are joining the strategic reserve that Russia has been forming since early July 2025. The source did not specify how many recruits are going to the strategic reserve as opposed to the frontline in Ukraine.
The Russian military command may have assessed that Russia could afford to create a strategic reserve after Russian losses began to decrease in the summer of 2025. The Ukrainian General Staff reported that Russia suffered roughly 32,000 to 48,000 casualties per month between January and July 2025—more casualties than the average reported monthly recruitment rate. The Ukrainian General Staff reported that Russia suffered roughly 29,000 casualties in August 2025 and 13,000 casualties in the first half of September 2025—the only months so far in 2025 with casualty rates below the average reported recruitment rate. ISW recently assessed that Russian territorial gains were less costly in May to August 2025 compared to the spring of 2025, as Russian forces sustained a lower casualty rate per square kilometer seized.[2] The reduced casualty rates in Summer 2025 may have convinced the Russian military command that Russia could afford to transfer some new recruits to a strategic reserve while still maintaining the tempo of offensive operations on the frontline in Ukraine. Changes in Russian tactics on the battlefield in the past few months likely contributed in part to the reduced casualty rates. Russian forces have been conducting assaults in smaller infantry groups and are increasingly employing small group infiltration tactics that seek to find and exploit weaknesses and holes in Ukraine’s undermanned defenses.[3] The formation of the strategic reserve may indicate that the Russian military command assesses that Russian forces will be able to continue their current rate of advance using these small group tactics that allow the Russian command to deploy fewer personnel to the frontline.
Reports that Russia is creating a strategic reserve further indicate that the Kremlin is not interested in ending its war against Ukraine but remains committed to achieving its war goals on the battlefield and may be preparing for a conflict with the North Atlantic Treaty Organization (NATO). Russian President Vladimir Putin has repeatedly put forward a theory of victory that assumes that Russian forces will be able to make slow, creeping advances on the battlefield indefinitely, enabling Russia to win a war of attrition against Ukraine.[4] The reported decision to create a strategic reserve and not deploy all new recruits to the frontline indicates that Putin and the Russian military command are content with the current rate of advance, even though Russian forces continue to only advance at a foot pace. The reported creation of a strategic reserve suggests that Russia plans to escalate offensive operations in Ukraine in the near-to-medium term rather than end the war. Russia may also be building out its strategic reserve as part of wider Kremlin preparations for a possible Russia-NATO conflict in the future, particularly as Russia intensifies its youth military-patriotic programs that aim to recruit Russian youth into the military in the years to come.[5]
Russia continues to test the limits of NATO’s air defenses over the Baltic Sea as Russia increases the frequency of its violations of NATO states’ airspace. The German Air Force reported on September 21 that NATO tasked the German Air Force with scrambling two German Eurofighters to intercept an unidentified aircraft without a flight plan or radio contact in international airspace over the Baltic Sea.[6] German forces later visually identified the plane as a Russian IL-20M reconnaissance aircraft. The German Air Force did not specify where over the Baltic Sea the incident occurred. Russia’s violation of standard operating procedures in international airspace is the latest in a string of aerial incursions into NATO territory since the Russian drone incursion into Polish airspace on the night of September 9 to 10.[7] US President Donald Trump reaffirmed on September 21 that the United States will “help” Poland and the Baltic States if Russia “keeps accelerating.”[8] ISW continues to assess that Russia is pursuing an aggressive campaign to test NATO air defenses and political will as part of a broader effort to collect actionable intelligence that Russia may then apply to a potential future conflict against NATO.[9]
Russian forces continue to develop drone technologies to increase the volume and precision of strikes against the Ukrainian near rear to further complicate Ukrainian logistics. A Kremlin-affiliated Russian milblogger claimed on September 21 that Russian forces developed fiber optic first-person view (FPV) repeater drones that could potentially quadruple the range of frontline drones.[10] Russia’s fiber optic drones are resistant to Ukrainian electronic warfare (EW) interference, and repeater drones contain a radio repeater that extends communication signals by acting as a relay station.[11] Russian drone operators may leverage the fiber optic repeater drones to protect other Russian drones from Ukrainian EW interference and increase the viability and precision of strikes against Ukraine’s near rear. The milblogger claimed that the newly developed fiber optic repeater drones can fly 50 to 60 kilometers, while traditional fiber optic drones are only able to fly 25 to 30 kilometers. Russia’s use of the longer-range repeater drones would allow Russian forces to strike more precisely and deeper into the Ukrainian near rear, particularly along ground lines of communication (GLOCs), further complicating Ukrainian frontline logistics. Russian milbloggers claimed on September 21 that Russian forces have created a “kill zone” (an area immediately near the frontline where a mass of tactical strike and reconnaissance drones pose an elevated risk to any equipment or personnel that enters that area) that extends roughly 45 kilometers from the frontline in both the Vovchansk and Kupyansk directions.[12] Ukrainian 11th Army Corps (AC) Spokesperson Lieutenant Colonel Dmytro Zaporozhets stated in a September 20 Wall Street Journal (WSJ) article that Russian forces are now systemically targeting Ukrainian logistics routes, depots, roads, and evacuation routes, but that Russian strikes of this nature were infrequent in 2024.[13] A sergeant of a Ukrainian reconnaissance unit reported to the WSJ that the nets that Ukrainian forces are constructing over roads to protect against Russian drone strikes are imperfect solutions, as Russian drone operators strike the poles that hold the nets up. Ukrainian Donetsk Oblast Military Administration Head Vadym Filashkin reported to the WSJ that Ukrainian forces are constantly repairing damage to anti-drone netting. ISW previously assessed that Russian forces are achieving some effects of battlefield air interdiction (BAI) with drone strikes against Ukrainian GLOCs that are enabling Russian advances in eastern Ukraine, and that Russia’s recent drone innovations are likely to enhance these BAI effects.[14]