The International Committee of the Red Cross (ICRC) said it had not yet obtained permission to visit the Olenivka prison where Ukrainian prisoners of war died in a strike on the facility.

In a statement, the ICRC said, "As of yet, we have received no official confirmation granting us access to visit the site or the prisoners of war affected by the attack, and, to date, our offer of material assistance has not been accepted."

In a statement late Saturday, the Russian Ministry of Defense said representatives from the UN and the ICRC had been invited to tour the area.

Kyiv has blamed the strike on Moscow which has, in turn, suggested Ukraine was behind the strike on the prison in a Russian-occupied part of eastern Ukraine.

The Russian army said 50 people died and 73 were wounded in the strike. Russian-back forces in the Donetsk region said 53 people had died.

Ukrainian President Volodymyr Zelenskyy said the bombing which left "more than 50 dead" was a "deliberate Russian war crime."

Here are the other main headlines from the war in Ukraine on July 31.

Zelenskyy: No Russian attack will go 'unanswered'

Ukrainian President Volodymyr Zelenskyy has condemned the latest Russian shelling of the southern city of Mykolayiv that killed a wealthy grain trader.

Olexiy Vadatursky, and his wife Rajissa, tragically died in the attack overnight into Sunday, officials said.

In his latest video address, Zelenskyy described the strike as “one of the most brutal bombings of Mykolayiv and the region.”

He vowed that no Russian attack “goes unanswered by our military and intelligence officials."

Russian troops were currently being moved from the east of Ukraine to occupied Kherson and Zaporizhzhya in the south, the president said. "But that won't help them."

Earlier, the Ukrainian General Staff said Russian troops were being transferred to Russian-controlled areas in the south of Ukraine.

Ex-Putin adviser in European hospital with severe illness

A former adviser to Russian President Vladimir Putin is in intensive care in an unspecified western European hospital on Sunday with a neurological disorder.

The initial diagnosis shows that Anatoly Chubais is suffering from Guillain-Barre syndrome, according to a Telegram message from a family friend and Russian TV personality Ksenia Sobchak.

Guillain-Barre is a rare disorder in which the body's immune system attacks the nerves. However, investigators are keeping an open mind following repeated cases where Putin's enemies were poisoned to death.

Sobchak cited Chubais' wife who said his condition was “unstable.” She did not say which clinic he was in.

Chubais, who resigned and quit Russia shortly after the invasion of Ukraine, did not state his reason for leaving. His was the highest level of a series of official resignations.

Chubais had most recently been Putin's envoy to international organizations on sustainable development.

He is well-known in Russia, having held high-profile posts since the early 1990s when he oversaw privatization efforts under Boris Yeltsin.

Hypersonic missiles for Russia's navy 'in the coming months' — Putin

Russian President Vladimir Putin said that the navy would be getting hypersonic Zircon cruise missiles in a matter of months.

"The delivery of these (missiles) to the Russian armed forces will start in the coming months," Putin said in St Petersburg, where he's attending celebrations marking Russia's Navy Day.  

"The Admiral Gorshkov frigate will be the first to go on combat duty with these formidable weapons on board," the Russian president added.

Hypersonic weapons travel through the upper atmosphere at a speed five times faster than the speed of sound, or 6,200 kilometers (3,853 miles) per hour.

Russia claims its Zircon missile travels at nine times the speed of sound and has conducted previous test launches from warships and submarines over the past year.

Putin also said that he had signed a new navy doctrine, the details of which were not yet published.

Ukrainian grain tycoon killed in Mykolaiv shelling

Oleksiy Vadatursky, 74, the founder and owner of Nibulon, a large Ukrainian agribusiness enterprise, was killed alongside his wife in a Russian strike on the Mykolaiv region, the local governor Vitaliy Kim announced. 

On Telegram, Kim said the couple had been killed in their home in Mykolaiv city during overnight shelling.

Forbes ranked him as Ukraine's 24th richest man with a fortune worth $430 million.

Nibulon specialized in the production and export of wheat, barley and corn. The firm has its own fleet and shipyard.

Ukraine denies drone attack on Russia's Black Sea fleet HQ

The spokesman for the coastal Odesa military region, Sergiy Bratchuk, says Ukraine was not behind an attack on the Russian Black Sea fleet headquarters in annexed Crimea.

Bratchuk dismissed claims Ukraine was behind the attack saying it was "sheer provocation."

"Our liberation of Crimea from the occupiers will be carried out in another way and much more effectively," Bratchuk wrote on Telegram.

The explosion took place in the city of Sevastopol on the Crimean peninsula which was annexed by Russia in 2014.

The mayor of the city said six people were injured in the blast.

Ukraine harvest could be halved this year, Zelenskyy warns

Ukraine’s president has warned of a significant shrinkage of his country’s harvest, up to "twice less" as the country continues to battle the Russian invasion for over five months.

President Volodymyr Zelenskyy said on Twitter on Sunday that his country’s main goal was to prevent a global food crisis. "Still grains find a way to be delivered alternatively," he said.

Ukraine was a major global source of wheat before the war. As per US Department of Agriculture figures, it produced 33 million tons in 2021, making it the world’s seventh-largest producer.

Earlier in July, a deal brokered by the UN and Turkey was reached between Russia and Ukraine to allow the export of grain from Ukrainian ports despite the war.

Turkish President Recep Tayyip Erdogan's spokesman Ibrahim Kalin told local broadcaster Kanal 7 on Sunday that the possibility of the first grain-exporting ship leaving Ukraine's ports on Monday was high. Kalin told the media outlet that the joint coordination center in Istanbul will probably complete the final work on the exporting routes very soon.

Russian official says Ukraine attacked fleet at Crimean port

A senior Russian official has accused Ukraine of attacking the Russian naval fleet in the Crimean port of Sevastopol on Sunday, as the Moscow-annexed region was preparing to celebrate Navy Day, an annual Russian holiday during which its fleets stage naval parades and honor its sailors.

The drone attack injured five fleet headquarters employees and resulted in the cancelation of festivities, said Mikhail Razvozhayev, governor of Sevastopol, home to Russia's Black Sea fleet. He accused Ukraine of "spoil(ing) the day for us."

"All celebrations have been canceled for security reasons," Razvozhayev said in a Telegram message. "Please remain calm and stay home if possible."

The alleged attack comes as Saint Petersburg prepares for a naval parade marking Navy Day, to be attended by President Vladimir Putin. The Russian president is also due to approve Russia's naval doctrine.

Crimea has been under Russian control since its annexation from Ukraine in March 2014.

More on the war in Ukraine

Ukraine's President Volodymyr Zelenskyy on Saturday ordered the evacuation of the eastern Donetsk region which has seen fierce clashes between Russian and Ukrainian forces. Read the story here.

The Russian energy giant Gazprom said it had stopped supplying gas to EU member state Latvia, accusing it of violating conditions for gas withdrawal. DW looks at the reasons and repercussions.

In a recent interview, the EU's foreign policy chief told DW that sooner or later Russia will crumble. Many international researchers also say the sanctions will eventually work. Others are less convinced. Read the details here.

ar, rmt/fb (dpa, Reuters)