The latest proposal involves DMZs in the Donbas and Zaporizhzhia. But DMZs have a mixed track record globally.

On the key question of Ukraine's eastern Donbas, Zelensky says a "free economic zone" is a potential option.

The Ukrainian president opens the door to creating a demilitarized zone supervised by 'international forces' in the part of the Donbas controlled by Kyiv, making the withdrawal of…