Ukrainian president Volodymyr Zelenskiy said on Wednesday he had visited the border with Belarus and Poland, where he praised the work of border guards.
"It is an honour for me to be here today to thank our border guards for protecting the state border," he wrote under video footage showing him meeting and addressing border guards.
It comes after Russian president Vladimir Putin visited the headquarters of Russian troops fighting in Ukraine in his second trip to Russian-held territories since March.
A video released by the Kremlin and broadcast by Russian state television showed Mr Putin visiting the command post for Russian forces in the southern Kherson region.
It showed Mr Putin arriving by helicopter to receive reports from military leaders about the combat situation.
The Russian leader then moved by helicopter to the headquarters of the Russian National Guard of the eastern Luhansk region to hear a report from commanders.
