Ukrainian President's advisor Mykhailo Podolyak suggested on Monday that a demilitarized zone should be established 100 to 120 kilometers deep inside Russia along its border with Ukraine as part of any post-war settlement. He stated on his official Twitter account, "The region will be necessary to protect Ukrainian territory from shelling." He emphasized that the key topic of the post-war settlement should be the establishment of safeguards to prevent a recurrence of aggression in the future.