Ukraine is targeting Russian soldiers who shoot at Europe's largest nuclear power station or use it as a base to shoot from, as G7 nations, fearing a nuclear catastrophe, called on Moscow to withdraw its forces from the plant.
Ukraine and Russia have traded accusations over multiple incidents of shelling at the Zaporizhzhia facility in southern Ukraine. Russian troops captured the station early in the war.
"Every Russian soldier who either shoots at the plant, or shoots using the plant as cover, must understand that he becomes a special target for our intelligence agents, for our special services, for our army," President Volodymyr Zelenskiy said in an evening address on Saturday.
Zelenskiy, who did not give any details, repeated claims that Russia was using the plant as nuclear blackmail.
The plant dominates the south bank of a vast reservoir on the Dnipro river. Ukrainian forces controlling the towns and cities on the opposite bank have come under intense bombardment from the Russian-held side.
Ukrainian presidential adviser Mykhailo Podolyak accused Russia of "hitting the part of the nuclear power plant where the energy that powers the south of Ukraine is generated."
"The goal is to disconnect us from the (plant) and blame the Ukrainian army for this," Podolyak wrote on Twitter.
The International Atomic Energy Agency (IAEA), which is seeking to inspect the plant, has warned of a nuclear disaster unless fighting stops. Nuclear experts fear fighting might damage the plant's spent fuel pools or the reactors.
United Nations chief Antonio Guterres has called for the establishment of a demilitarised zone around the Zaporizhzhia facility, which is still being run by Ukrainian technicians.
Kyiv has said for weeks it is planning a counteroffensive to recapture Zaporizhzhia and neighbouring Kherson provinces, the largest part of the territory Russia seized after its Feb. 24 invasion and still in Russian hands.
Russian and Ukrainian forces earlier fought for control of Chernobyl, the still-radioactive site of the world's worst nuclear accident, also raising fears of a disaster.
Diplomatic rift deepens
Russia's invasion, which it calls a "special military operation" to demilitarise and "denazify" its smaller neighbour, has pushed Moscow-Washington relations to a low point, with Russia warning it may sever ties.
The United States has led Ukraine's Western allies in supplying it with weapons to defend itself and punitive sanctions against Moscow.
A senior Russian official on Friday said Moscow had told Washington that if the U.S. Senate passed a law singling out Russia as a "state sponsor of terrorism", diplomatic ties would be badly damaged and could even be broken off.
On Saturday a senior Russian foreign ministry official warned that any seizure of Russian assets by the United States would completely destroy bilateral relations, TASS reported.
"We warn the Americans of the detrimental consequences of such actions that will permanently damage bilateral relations, which is neither in their nor in our interests," said Alexander Darchiev, head of the ministry's North American Department. It was not clear which assets he was referring to.
Darchiev said US influence on Ukraine had increased to the degree that "Americans are increasingly becoming more and more a direct party in the conflict".
The United States and Europe, wary of being dragged directly into the war, have refused Ukraine's request to establish a no-fly zone to help it protect its skies from Russian missiles and warplanes.
Ukraine grain ships
Two more ships carrying grain left Ukraine's Black Sea ports on Saturday, Turkey's defence ministry said, bringing to 16 the number of vessels to depart under a UN-brokered deal aimed partly at easing a global food crisis.
Ukraine's infrastructure ministry said on Saturday that 16 ships carrying 450,000 tonnes of agricultural products had departed from Ukrainian sea ports since early August under the deal, which ensured safe passage for vessels.
The agreement, signed by Ukraine, Russia, Turkey and the UN in July amid warnings of possible outbreaks of famine, allowed grain exports from Ukraine's Black Sea ports to resume after being stalled for five months due to the war.
Zelenskiy said that in less than two weeks, Ukraine had managed to export the same amount of grain from three ports as it had done by road for all of July.
"This has already made it possible to reduce the severity of the food crisis," he said on Saturday.
Ukraine hopes to increase its maritime exports to over 3 million tonnes of grain and other farm products per month in the near future.
Ukraine and Russia are major grains exporters. The blockage of Ukrainian ports has trapped tens of millions of grain in the country, raising fears of severe food shortages and even outbreaks of famine in parts of the world.