Unpacking the Russian Troop Buildup along Ukraine’s Border

On March 31, U.S. European Command raised its awareness level to “potential imminent crisis” in response to estimates that over 100,000 Russian troops had been positioned along its border with Ukraine and within Crimea, in addition to its naval forces in the Sea of Azov. This deployment, representing the highest force mobilization since Russia’s annexation of Crimea and military incursion into Eastern Ukraine in 2014, came on the heels of a sharp escalation in fighting along the line of control separating Ukrainian forces from Russian-backed separatists in Donbas in March. Ukraine has been under extraordinary pressure in light of the scale and scope of this mobilization. On April 13, Russian minister of defense Sergei Shoigu stated that this mobilization constituted a “response to threatening activities” by NATO. However, NATO has not significantly shifted its forces other than to continue preparations for a previously notified multistage annual exercise, DEFENDER-21, which involves approximately 30,000 forces from 27 nations and began in March.

On April 22, the Russian government appeared to turn down the heat on these deployments, with Minister Shoigu announcing a drawdown of the exercise and ordering troops to return to their permanent bases by May 1, to include the 58th Army of the Southern Military District, the 41st Army of the Central Military District, as well as the 7th and 76th Airborne Assault and 98th Airborne divisions, according to the statement. Importantly, the equipment and weapons of the 41st Army are to remain at Pogonovo, a military training ground 17 kilometers south of Voronezh. According to Shoigu, they will be used in Russia’s annual Zapad exercises in Western Russia and Belarus in September. Moreover, all troops should remain “in a state of readiness for an immediate response in case of the unfavourable development,” he said, referring to NATO’s DEFENDER-21 exercises.



Russia’s thermostat (de)mobilization—turning the heat up dramatically and then abruptly lowering it—has kept NATO and Ukraine, tense and off-balance. The military “exercises”, allegedly involving two armies and three paratrooper divisions, are worth unpacking.

Satellite images of the Pogonovo training facility captured on April 10 shed light on the scale of the deployment and nature of military equipment involved. The images show two motorized rifle brigades and additional, likely division-level elements, including a field hospital, troop housing, and several unidentified troop deployments. Additional imagery indicates that the units arrived sometime between March 24 and April 9, marking a relatively rapid deployment and setup. Identified within the cantonments of the two motorized rifle brigades were tank and rifle battalions and multiple rocket launcher (MRL), air defense, and short-range ballistic missile (SRBM) batteries. One of the two cantonments also included probable engineering and chemical defense companies. To the east of the two brigades is an unidentified troop deployment under tarps and netting, which may serve as a headquarters.

Close-ups of the military assets at Pogonovo training facility. Click to expand.

Though nominally a readiness check, the scale of the mobilization to Pogonovo and Crimea raised fears that Russia was planning a more permanent staging presence along the border with Ukraine and a possible escalation. Russian forces deployed for over five weeks—much longer than Russia’s largest annual training exercises. While Russia does occasionally exercise long-distance deployments of troops and equipment from distant military districts, April’s mobilization has no recent parallel.
The announced drawdown indicates a significant deescalation. However, until Russian troops actually leave Pogonovo, the situation will remain tense. The nature of their deployment observed in satellite imagery does not clearly indicate offensive or defensive postures, but rather one of readiness. Available images show the units can move out of their current cantonments with relative ease and speed to conduct either offensive or defensive operations with the currently deployed units and supplies. Extended operations appear unlikely, as they would require additional logistic support from division, corps, or army level. We estimate that either of the motorized rifle brigades in the imagery would need to be resupplied after only moderate travel every three to seven days with no combat. In combat, and depending upon intensity, the same motorized rifle brigade could require resupply every one to two days.
While observers have offered a variety of possible explanations for Russia’s motives, Pogonovo’s buildup and its more northernly location forced Ukraine and the West to grapple with the most pessimistic scenario: that Russia could launch a broader offensive on Ukraine not contained to the existing line of control to the south. The base is 250 kilometers northeast of Ukraine-controlled territory in Luhansk region, but over 400 kilometers from the northernmost tip of the separatist-controlled Lugansk People’s Republic in Ukraine, creating greater offensive optionality for Moscow. Some have argued that Russian “exercises” could be designed to conceal the movement of troops and supplies into separatist-controlled Donbas as part of a calculated but deniable escalation by Moscow, but Pogonovo is an unlikely staging site for such an operation, raising the specter of an attack on Ukraine-controlled Luhansk.
Additional close-ups of the Pogonovo training facility. Click to expand.
The April 10 images make clear that there are presently enough Russian troops to credibly threaten Ukraine. The planned departure of troops from Crimea and Pogonovo would change this dynamic. However, the decision to keep a significant arsenal in Pogonovo through the summer suggests Russia’s final force posture along Ukraine’s border remains unsettled. The time required for Russian troops to redeploy to the camp and take up an offensive posture will be significantly reduced. 

Although Washington aspires to a more “stable, predictable” relationship with Moscow, the military buildup in and around Ukraine has undermined this goal. The announced troop drawdown is a welcome step towards stability, but for now, the situation remains unpredictable.
Special thanks to Jennifer Jun for her research support. Imagery markups by William Taylor.
Cyrus Newlin is an associate fellow with the Europe, Russia, and Eurasia Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Heather Conley is senior vice president for Europe, Eurasia, and the Arctic and director of the CSIS Europe, Russia, and Eurasia Program. Matthew P. Funaiole is a senior fellow for data analysis with the iDeas Lab and senior fellow with the China Power Project at CSIS. Joseph S. Bermudez, Jr., is a senior fellow for imagery analysis (non-resident) with the CSIS iDeas Lab and Korea Chair.
Commentary is produced by the Center for Strategic and International Studies (CSIS), a private, tax-exempt institution focusing on international public policy issues. Its research is nonpartisan and nonproprietary. CSIS does not take specific policy positions. Accordingly, all views, positions, and conclusions expressed in this publication should be understood to be solely those of the author(s).
© 2021 by the Center for Strategic and International Studies. All rights reserved.
Matthew P. Funaiole
Vice President, iDeas Lab, Andreas C. Dracopoulos Chair in Innovation and Senior Fellow, China Power Project

Heather A. Conley

Cyrus Newlin

Cyrus Newlin

Former Associate Fellow, Europe, Russia, and Eurasia Program