Russia said the Ilyushin Il-76 military plane was carrying 65 captured Ukrainian soldiers. Yusov said Kyiv does not have enough evidence to believe that.

Yusov added that two other Russian military transport planes An-26 and An-72 were simultaneously in the airspace.

"Unfortunately, we can assume various scenarios, including provocation, as well as the use of Ukrainian prisoners as a human shield for transporting ammunition and weapons," he said.

Yusov reiterated that Belgorod airfield was actively used by Russia for military supplies.

During the last prisoner exchange, when air transport was used, Russia asked Ukraine to secure air space, he added.

"This time, the aggressor state did not make such requests either in written or verbal form," he said.

(Reporting by Yuliia Dysa; Editing by Alison Williams, Alexandra Hudson)