Frontline report: Ukraine prepares for likely Russian assault from Belgorod region

Day 761: 25 March

Today, there are a lot of updates from the Kupiansk direction in northeastern Ukraine’s Kharkiv Oblast.

In the wake of the increased activity along the border of the Belgorod region, Russian military commanders and high-ranking officials started demanding the creation of a “sanitary zone.”

The calls for the establishment of the demilitarized zone to protect the Russian border has brought back to the forefront a potential new Russian offensive from the north.

Today, we will examine the prospects of this offensive, given that the main attack direction in the area is north of Kupiansk, particularly the one located between the Siverskyi Donets and the Oskil rivers.

As you may remember, Kupiansk and the territories located on the eastern bank of the Oskil River are the core objectives for the Russian political aims of capturing and securing the complete borders of the different invaded regions in the present war and among those, primarily Luhansk and Donetsk.

Fears of an offensive from the north have also multiplied after the recent decision of the Ukrainian regional authorities to evacuate people from dozens of settlements near Kupiansk, as a consequence of the continuous indiscriminate artillery attacks on the civilian population.

Ukrainian forces have been preparing for many months for a possible Russian offensive in this region, and according to various statements, this is one of the best-prepared areas for defense in all of Ukraine. As an example, Russian forces have been trying for more than a year to reach the city of Kupiansk directly without success.

If we look at the map of defensive lines, Ukrainian forces have arranged here two main defensive lines, each connecting a network of fortifications, which provide support to each other.

The northernmost line is about 70 km long and faces this entire border segment, including the two main border crossings. The second line is slightly shorter and runs in parallel, about 50 km south, from the Siverskyi Donets River to the north of Kupianks city. In addition, the two lines are connected by a road linking their approximate midpoints.

Firstly, an attack from the north would have to face this extremely well-prepared first defensive line. The location of the rivers implies that even if they managed to break the line at some point, they would inevitably have to face the second line.

If we look at the topographic map, we can see that an attack from the northwest has the added difficulty of fighting uphill in the first stretch after the border.

Therefore, this option seems particularly adverse to the Russian forces.

A second option would be to establish an additional attack vector from Dvorichna, trying to quickly reach the road linking the defensive lines in an attempt to isolate the first defensive line. It is not an easy undertaking, but if successful, a possible continuation is to completely encircle both Kupiansk and the second line, trying to isolate them and appearing from the rear all the strong points protecting the city to finally surrender them all.

One must consider the magnitude of resources necessary for an offensive of these characteristics, which implies mechanized advances of tens of kilometers, given that the actual advances here for months have been only marginal gains of a few hundred meters. However, the Russian command could play its card by taking advantage of delays in Western aid in artillery supplies and especially by achieving localized air superiority to undermine Ukrainian fortifications with the use of FAB glider bombs.

The main option for the Ukrainians in this second hypothesis is to reinforce the defense of the segment in front of the Dvorichna pass, up to the road linking the defensive lines, trying to make it as difficult as possible to lose control of this road. In addition, they should consider alternative supply routes, both for the defensive lines and for Kupiansk from the south.

As a third hypothesis, in addition to all the above, Russian forces could attack from the north to fix the forces of the two defensive lines, focusing on encircling Kupiansk in the first instance. This could be done in theory by increasing the combat force from the already active areas, but especially by launching an attack vector from Dvorichna and moving down from there to the south to engage only the eastern end of the second defensive line.

In the event of breaking the defense at this point, going down to Kupiansk to encircle it seems feasible.

The city encirclement would automatically compromise the logistics of the entire line facing the Russians east of the Oskil River, complicating the situation for the Ukrainian forces in this area to a large extent.

The options here for the Ukrainians would be to reinforce again the entire area near the Dvorichna Pass, as well as to increase defenses and fortifications in the western and northwestern part of the city of Kupiansk, and to improve logistical supply options from the south of the town.

Overall, the recent demands of the Russian leadership for a sanitary zone, the evacuation of numerous villages in the Kharkiv region, and the fact that sooner or later, the Russians need to address the seizure of Kupiansk and the eastern bank of the Oskil River with more significant resources have raised the alarm of a potential new Russian offensive from the north in the coming months.

Given the high level of readiness of the defensive lines in this region, it is clear that this will require Russian forces to build up a huge mass of forces, based on the difficulties already encountered in recent months.

The recent announcement of the creation of two new combined Russian armies and rumors of a possible new mobilization in Russia increase speculation in this regard.

Let us hope that in the event of this new offensive, the Ukrainian forces will have received the promised Western aid to achieve the best defensive preparation level possible.

In our daily frontline report, we pair up with the military blogger Reporting from Ukraine to keep you informed about what is happening on the battlefield in the Russo-Ukrainian war.