Russian media write about this with reference to the press secretary of the President of Russia Dmytriy Peskov. Like, it's not Russia holding a referendum, but local residents. Thus, the Kremlin is trying to legalize the processes in the occupied territories.

According to the Constitution of Ukraine, the protection of the sovereignty and territorial integrity of Ukraine is the business of the entire Ukrainian people, and issues of changing the territory of Ukraine are resolved exclusively by an all-Ukrainian referendum. Ukrainian law prohibits holding elections or referendums during martial law. Any attempt to hold a referendum in the temporarily occupied territories is illegal and violates international law. The decision on the ownership of Ukrainian territories can be made and recognized by other states only if all the norms of the current Ukrainian legislation are observed.