Kiev, Sep 11 : The sixth power unit of the Zaporizhzhia Nuclear Power Plant (ZNPP) was disconnected from the power grid at 3:41 p.m. on Sunday. Preparations are underway for its cooling and transfer to a cold state, said Ukraine's national nuclear energy generating company -- Energoatom. Energoatom has said that for the past three days, the sixth power unit has been working in island mode at a critically low capacity, feeding only the plant's own needs, as all of the ZNPP communication lines with the Ukrainian power grid were damaged due to Russian shelling. "On September 10 evening, after operational capacity of one of these communication lines was restored, it became possible to supply ZNPP with auxiliary power from the Ukrainian power grid. Therefore, a decision was made to shut down power unit 6 and transfer it to the safest state -- cold shutdown. In the event of repeated damage to the lines of communication with the power grid, the risk of which remains high, the ZNPP's auxiliary power supply will be provided by diesel generators, and their operation is constrained by their technology and the amount of available diesel fuel." On September 1, the International Atomic Energy Agency Mission arrived at the ZNPP in occupied Enerhodar, Ukrainska Pravda reported. On September 5, four of the six participants of the IAEA mission completed their mission at the station, while two representatives of the organisation were to remain there On September 6, the IAEA released a report on a visit to Enerhodar and confirmed that Russia had stationed military personnel and equipment at the ZNPP. Sergiy Kyslytsya, Ukraine's Permanent Representative to the UN, said that the Russians tried to put pressure on IAEA Director General Rafael Grossi while he was preparing the report on the ZNPP. /IANS