Russian attacks were reported across large areas of Ukraine on Thursday, with shelling and missile strikes damaging infrastructure, including electricity supplies to Europe's largest nuclear plant, Ukrainian officials said.
The Zaporizhzhia nuclear power plant in southern Ukraine has again been disconnected from the power grid after Russian shelling damaged the remaining high voltage lines, leaving it with just diesel generators, Ukraine nuclear firm Energoatom said.
The plant, in Russian hands but operated by Ukrainian workers, has 15 days' worth of fuel to run the generators, Energoatom said. Its reactors need the power to keep the fuel inside cool and prevent a meltdown.
A senior official in Moscow said Russian special forces had prevented a Ukrainian attack on the plant. Russian Security Council Secretary Nikolai Patrushev, a close ally of President Vladimir Putin, also said Ukrainian forces "continue to shell the Zaporizhzhia nuclear power plant with Western weapons which could lead to a global catastrophe."
Both sides have repeatedly accused the other of shelling the plant, accusations that both deny.
Russian strikes were also reported in Kriviy Rih, in central Ukraine, and in Sumy and Kharkiv, in the northeast. There was heavy fighting in the eastern regions of Luhansk and Donetsk.
"The enemy is trying to keep the temporarily captured territories, concentrating its efforts on restraining the actions of the Defence Forces in certain areas," Ukraine's general staff said Thursday.
Reuters was unable to verify the battlefield reports.
Russia has said it has targeted infrastructure as part of what it calls its "special military operation" to degrade the Ukrainian military and remove what it says is a potential threat to Russia's security.
As a result, Ukrainian civilians have endured power cuts and reduced water supplies in recent weeks. Russia denies targeting civilians, though the conflict has killed thousands, displaced millions and left some Ukrainian cities in ruins.
Foreign ministers from the G7 group of rich democracies will discuss how best to coordinate further support for Ukraine when they meet on Thursday in Germany.
British envoy summoned
On Thursday morning, the British ambassador was summoned to the foreign ministry in Moscow over Russia's claims that Britain was involved in a Ukrainian drone strike on Russia's Black Sea Fleet in Crimea.
Ambassador Deborah Bronnert was in the ministry for around 30 minutes, a Reuters journalist at the scene said. A small crowd outside chanted anti-British slogans and held up placards reading "Britain is a terrorist state."
Russia temporarily suspended participation in a U.N.-brokered Black Sea Grain Initiative on Saturday after what it said was a major drone attack on vessels in the Bay of Sevastopol on the Crimean peninsula, which Russia annexed from Ukraine in 2014.
Russia's defense ministry said the attack was carried out under the guidance and leadership of British navy specialists, an assertion Britain has dismissed as false.
Putin has also accused Britain of being behind attacks on the Nord Stream pipelines in September that have put the multi-billion dollar gas link between Russia and Europe out of use, possibly permanently.
On Wednesday, Russia resumed participation in the grain deal freeing up exports from Ukraine, after Turkey and the United Nations helped keep Ukrainian grain flowing for several days without a Russian role in inspections.
Russia's defense ministry justified the resumption by saying it had received guarantees from Ukraine that it would not use the Black Sea grain corridor for military operations against Russia.
Ukraine said it had made no new commitments beyond the terms of the deal agreed upon in July.
Seven ships carrying agricultural products left Ukrainian Black Sea ports Thursday, Ukraine's infrastructure ministry said.
The vessels were loaded with 290,000 tonnes of food products and were headed towards European and Asian countries, it said in a statement without elaborating.
The grain deal had helped alleviate a global food crisis by lifting a de facto Russian blockade on Ukraine, one of the world's biggest grain suppliers. The prospect of it collapsing this week revived fears of a worsening food crisis and rising prices.
The prices of wheat, soybeans, corn and rapeseed fell sharply on global markets after Russia's announcement.
Kherson counteroffensive
In the south, a Ukrainian counteroffensive has left Russian forces fighting to hold their ground around the city of Kherson, where Russian-installed authorities were urging residents to evacuate, the Ukrainian military said.
Kherson was the first city to fall to Russian forces, after they launched their invasion on Feb. 24.
Residents who had collaborated with occupying forces were leaving and some departing medical staff had taken equipment from hospitals, the Ukraine military said.
Residents of the town of Nova Zburivka had been given three days to leave and were told that evacuation would be obligatory from Nov. 5.
Russian authorities have repeatedly said Ukraine could be preparing to attack the massive Kakhovka dam, upriver on the Dnipro, and flood the region. Kyiv denies that.
"Obviously, we are afraid of this. That is why we are leaving," resident Pavel Ryazskiy, who was evacuated to Crimea, said of the possibility the dam could be destroyed.