Ukraine s Zaporizhzhia nuclear power plant is still disconnected from the grid after fires broke out around the plant on Thursday.
Ukrainian authorities and international experts have warned of the potential for nuclear catastrophe because of fighting around the plant.
Volodymyr Zelenskiy said that the world has only been able to escape a radiation disaster on Thursday.
The problem with the electricity supply to the plant appears to be unresolved as of Friday morning. The plant was disconnected on Thursday when a blaze affected the fourth and last connection into the plant's reactors. Three other lines had already been taken out during the war.
Satellite images released by Ukraine's Radio Liberty showed plumes of smoke rising near the plant.
Energoatom, Ukraine's state nuclear agency said work was under way to restore the plant's connection to the grid and the plant's own electricity needs were supplied through a power line from Ukraine's electricity system.
Energoatom said it could not comment on the safety of the equipment or systems.
The nuclear plant, Europe's largest, relies on electricity to keep its reactors cool. It's dangerous to disconnect the plant from the grid because it increases the risk of catastrophic failure of the electricity-run cooling systems for its reactors and waste fuel rods.
The plant received supplies of electricity from one remaining backup line connected to the nearby conventional power plant during the outage, Energoatom said. There were three of these lines before the war, but two of them have been cut.
If all the external connections go down, the plant must rely on diesel-fuelled generators for power. If the break down, engineers have only 90 minutes to stave off dangerous overheating.
Russia and its occupying authorities are facing a lot of challenges in running their newly conquered territories as a result of Russia taking over the plant.
Video footage released on Thursday shows the occupying authorities attempting to build a pontoon bridge across the river to replace the Antonovskiy bridge struck by Ukrainian forces last month, rendering it unusable.
The Russian authorities are going to hold referendums in the newly occupied parts of southern Ukraine, although it appears they will take different forms and may be conducted on different dates.
The mayor-in-exile, Ivan Fedorov, said that pollsters will go door-to- door instead of voters attending polling stations in the occupied-Zaporizhzhia region.
The authorities are trying to operate while they are apparently being attacked from within. Russian news agency RIA reported that a bomb exploded in the building where the referendum was planned and Russian passports were issued.
The previous day, on Ukraine's independence day, the head of another occupied city nearby, Ivan Sushko, was killed by a car bomb, another member of the Zaporizhzhia occupying authorities reported on Telegram.
Sushko's death is the latest in a string of assassinations that have targeted members of the occupying authorities. On 23 August, Ihor Telehin, the deputy head of the internal policy department for the occupying Kherson region, was also targeted with a bomb but survived, according to Russia's state news agency, Tass.