The UN chief said they also discussed security at Europe’s largest nuclear plant, where he said shelling had stopped for the past three days, and prisoners of war. “I think there are still negotiations,” he said. “I strongly hope that the problem of prisoners of war will be completely resolved, and I strongly hope that all prisoners of war on both sides will be exchanged.” Guterres told a news conference that Putin said a fact-finding mission he appointed at the request of Russia and Ukraine to investigate the killings at Olenivka prison in a separatist region of eastern Ukraine on July 29 would be able to go there “by any means choose, and this is a very important aspect.’ The warring nations accuse each other of carrying out the attack in which separatist authorities and Russian officials said 53 Ukrainian prisoners of war were killed and 75 wounded. Guterres said the call to Putin followed his meeting with Ukrainian President Volodymyr Zelenskyy in Lviv on August 18 and regular calls to Zelenskyy’s chief of staff Andriy Yermak. Putin will not attend next week’s annual gathering of world leaders at the United Nations General Assembly, which Guterres said is taking place “at a time of great danger.” “Our world is ravaged by war, wracked by climate chaos, wracked by hate and shamed by poverty, hunger and inequality,” the secretary-general said. The war in Ukraine is not only destroying the country but dragging down the global economy, Guterres said, and hopes for a peace deal are “slim”. He added: “I’d be lying if I said I hoped it would happen soon.” Despite the July 22 agreement to start shipping Ukrainian grain from Black Sea ports and bring Russian food and fertilizer to world markets, Guterres said, “there is a risk of multiple famines this year.” The secretary-general said high fertilizer prices have already reduced food planting, which is why it is critical to increase Russian exports of ammonia — a key ingredient in fertilizers — and why talks are underway on possible shipment through Black Sea ports. Sea currently used to transport grain from Ukraine. UN Trade Chief Rebeca Grynspan, who leads the team trying to facilitate seamless global access to Russian food and fertilizer, told reporters on Tuesday that Russia reported a 12 percent increase in food exports from June to July, but fertilizer exports continue to decline despite being covered by the agreement, with insurance, financing and shipping issues. Guterres said he discussed with Putin the “dramatic situation in fertilizers” and obstacles to transporting ammonia from Russia. “We risk having a crisis in the fertilizer market,” the UN chief said. “We have news from various parts of the world that cultivated areas are much smaller than last cycle, which means that we risk in 2022 a real food shortage.” “Thus, removing the barriers that still exist in relation to the export of Russian fertilizers is absolutely necessary at this time,” he said. The July 22 grain deal expires in 120 days, and Guterres said “a very important dialogue” is taking place between the UN and Russia and between the UN and Ukraine, “and we’re looking not only at maintaining the grain deal but also its expansion. ” And one example is possibly sending Russian ammonia through the same Black Sea canal as Ukrainian grain, he said. Greenspan, who heads the UN Conference on Trade and Development, said fertilizer is needed by October and November, the latter, for the planting season in the northern hemisphere. On the issue of the Zaporizhzhia nuclear power plant in southeastern Ukraine, Europe’s largest, the head of the UN nuclear watchdog said on Monday that he has started consultations with Ukraine and Russia over his call for a “nuclear safety buffer zone ” around the facility, both sides seem interested. Rafael Grossi, the director general of the International Atomic Energy Agency, said the two sides appeared to be interested. He made the proposal last week after leading a team of inspectors to the nuclear plant and leaving two of them there to monitor its safety. The factory has been occupied by Russian forces, but has been operated by its Ukrainian employees since the beginning of the war. The Zaporizhzhia plant was reconnected to Ukraine’s electricity grid over the weekend, allowing engineers to shut down its last functioning reactor in a bid to avert disaster as fighting raged in the region. Guterres said that according to his latest information, electricity is being provided to guarantee the cooling of the reactors and other necessary electricity. “We have gone three days without bombing,” he said.