Russia has "certain units" on the border with Ukraine's Sumy Oblast, and an attack in this sector "can never be ruled out," State Border Guard Service spokesperson Andrii Demchenko told Radio Free Europe/Radio Liberty's (RFE/RL) on May 21.
Kyrylo Budanov, Ukraine's military intelligence chief, suggested in mid-May that Russian forces may launch an offensive in Sumy Oblast similar to the ongoing one in Kharkiv Oblast when the conditions are more favorable.
Russia may try to attack the region even if it lacks the forces, Demchenko said.
"It is in order to stretch the front line, the line of active combat operations, and actually stretch (Ukraine's) defense forces," he added.
"We also need to understand that the length of the border with our enemy is quite large. It is more than 560 kilometers (around 350 miles) in Sumy Oblast alone."
Ukraine should be prepared for "any situations" and continue to build up its defense capabilities, Demchenko said.
Since the Russian-occupied parts of Sumy Oblast were liberated in early April 2022, the region has been experiencing daily shelling and attacks from across the border, as it is located on Ukraine's northeastern border with Russia.
Ukrainian authorities ordered further evacuations from the region amid intensified attacks.
Kateryna Denisova
