Ukraine's foreign ministry on Thursday said that Russian attempts to hold elections in occupied territories or to force regional residents to head to the polls would be "illegal" — a sentiment echoed by NATO chief Jens Stoltenberg in a separate briefing, Reuters reports.
Russia's presidential election is slated to take place over March 15-17.
Meanwhile, two people were killed and several were injured in Ukrainian attacks on the Russian region of Belgorod, its governor said. CNBC could not independently verify the details.
Earlier, the White House said it had no reason to adjust the U.S.' "nuclear posture" after comments by Russian President Vladimir Putin Wednesday in which he said his country was "technically" ready for nuclear war.
In other news, Russian-installed officials at the Zaporizhzhia nuclear power plant in southern Ukraine accused Ukraine's armed forces of shelling critical infrastructure at the plant on Thursday.
Russia has occupied the plant since March 2022, with the nuclear facility being a focal point of tensions and skirmishes between Ukrainian and Russian forces. CNBC was unable to verify the latest claims.