Any referendums on joining Russia in Russian-occupied Ukrainian territories would destroy any remaining window for talks between Kyiv and Moscow, Ukrainian publication Liga.net cited the Ukrainian president's office spokesman as saying on Tuesday.
"Without the referendums, there is still the smallest chance for a diplomatic solution. After the referendums - no," Liga.net quoted Serhiy Nykyforov as saying.
He made the comments in response to Russian-installed officials in four occupied Ukrainian regions announcing plans for referendums over the next week on formally joining Russia.