UN chief Antonio Guterres says he is "gravely concerned" about the nuclear plant in Zaporizhzhia, which is under Russian control
He was speaking after meeting Ukraine and Turkey's leaders in Ukraine to discuss finding a political solution to the war
Workers at the nuclear plant say artillery strikes are becoming more powerful and call for an end to "irresponsibility and madness"
Guterres has called for a demilitarisation of the plant, the biggest in Europe, which Russia has rejected
Guterres, Volodymyr Zelensky and Recep Erdogan have also been talking about efforts to increase Ukraine's grain exports
In other developments, Russia has continued its shelling of residential areas in Kharkiv, with 17 people killed overnight, according to the regional governor
That's all from us on Ukraine for today, but you can read more in some of our latest stories on the war.
Today's coverage was brought to you by Alys Davies, Aoife Walsh, George Wright, James FitzGerald, Heather Sharp and Alex Therrien.
Image source, EPAThe leaders of Turkey, Ukraine and the UN held a press conference after talks
We'll be bringing our coverage to today's events in Ukraine to a close soon, but first, here's a look back at some key developments.
Explosions hit an area near a Russian military airport in the annexed Ukrainian peninsula of Crimea on Thursday, according to Reuters.
At least four explosions struck the airport of Belbek, north of Sevastopol, the news agency reported, citing three local sources.
Ukraine has not confirmed it was behind the attack and the BBC cannot independently verify the claim.
The explosions follow a string of attacks against Russian military sites and equipment in Crimea over the last week, which Ukraine has not claimed responsibility for.
After one such attack, Ukraine’s defence minister, Oleksiy Reznikov, suggested careless Russian soldiers could be to blame, warning the country's troops to not “smoke in dangerous places”.
Around the time Thursday's attack was reported, Ukraine's defence ministry tweeted, external "smoking kills" - an apparent reference to Reznikov's apparently tongue-in-cheek remarks.
Russia has also not confirmed Thursday's attack.
The governor of Sevastopol said Russian anti-aircraft forces downed a Ukrainian drone but said no damage had been done.
Image source, Getty ImagesRussian troops are accused of using the power plant as a military base - but also attacking it
UN chief Antonio Guterres has said he is "gravely concerned" about the nuclear plant in Zaporizhzhia, which is under Russian control.
What's been happening there since the war started?
Image source, EPAThe Ukrainian president (left) says he's agreed the parameters of any inspection of the nuclear plant with the UN chief (right)
More from President Zelensky, who's given his nightly video address.
There's "no objective obstacle" to any visit to the Zaporizhzhia nuclear power plant by the International Atomic Energy Agency (IAEA), he says.
Both Russia and Ukraine accuse each other of shelling the vast power plant, which is under Russian occupation, risking a nuclear accident.
In his video, Zelensky says it would be possible for IAEA representatives to assess the site having safely travelled via Ukrainian-held territory.
He earlier said he'd agreed the parameters of a potential visit with UN chief Antonio Guterres.
Zelensky says any denial of an IAEA mission by Moscow would mean the Kremlin was "destroying the international order".
David Brown
BBC News Visual Journalism Team
New figures suggest that the US is still by far the biggest donor of military aid to Ukraine.
The Kiel Institute for the World Economy says Washington committed to spending more than $25bn between 24 January and 1 July.
The UK has committed the second largest amount, with Poland and Germany third and fourth in the list.
Image source, .The figures do not take into account amounts committed but not actually spent, so it is possible that they don't give a full picture of what help is reaching Ukraine's armed forces.
Separately, the researchers looked at overall aid commitments in July, including financial and humanitarian help to Ukraine.
They said that last month:"Donor countries initiated almost no new aid, but they did deliver some of the already committed support such as weapon systems.”
An ammunition depot is on fire near the village of Timonovo in the Belgorod region of Russia, near the border with Ukraine, according to the local governor.
Writing on Telegram, Vyacheslav Gladkov said there were no casualties, but that residents in nearby areas had been evacuated for their own safety.
He added that the cause of the fire is under investigation.
The BBC is unable to verify the incident.
Nuclear watchdog needs access to Ukraine power plant - Ukraine's ambassador to the IAEA
Ukrainian President Volodymyr Zelensky says he and UN Secretary General Antonio Guterres have agreed the parameters of a possible mission of the International Atomic Energy Agency (IAEA) to the Zaporizhzhia nuclear plant.
Following talks with Turkey's leader and Guterres in Lviv, Zelensky told a news conference Russia should immediately withdraw its forces and stop shelling from the nuclear power plant.
He said a possible IAEA visit should be done "legally via territory free from the occupiers".
Ukraine’s representative to the IAEA told the BBC a team of inspectors must be allowed into the facility as soon as possible.
Yevhenii Tsymbaliuk said the best option would be to remove Russian forces and weapons from the site - the largest nuclear complex in Europe - and for Ukrainians to regain full control of the power plant.
Ukrainian President Volodymyr Zelensky has ruled out a peace deal with Russia unless it withdraws its troops from Ukraine.
Speaking after talks with Turkey's President Recep Tayyip Erdogan and UN Secretary General Antonio Guterres in Lviv, Zelensky told reporters he was "very surprised" to hear from the Turkish leader that Russia was "ready for some kind of peace".
He adds: "First they should leave our territory and then we'll see."
Image source, Kharkiv Regional State AdministrationThe death toll in Kharkiv, in north-eastern Ukraine, has increased to 17 people after Russian shelling hit a number of residential buildings, according to local governor Oleh Synehubov.
As well as the 10 people who had already been pronounced dead, rescuers have now recovered a further seven bodies from the rubble, Synehubov wrote in a message on Telegram.
Among the dead was a boy born in 2009, he added.
Forty-two people were also injured in the rocket attacks, he said.
Attacks also hit the city of Krasnograd in the Kharkiv region - where a couple were killed and their 12-year-old daughter was seriously injured, Mr Synehubov said.
Hugo Bachega
BBC News, Dnipro
Image source, Getty ImagesThe UN and Turkey helped broker the only diplomatic breakthrough in this war so far - a deal that allowed Ukraine to resume its exports after a months-long Russian blockade that led to a global food crisis.
Antonio Guterres, the UN Secretary General, was personally involved in the negotiations; Turkey is hosting the centre that co-ordinates the deal, including with inspections of ships.
It’s a delicate arrangement. After meeting the Ukrainian and Turkish presidents, Guterres urged all sides to continue working “in good faith” for the deal to hold.
President Erdogan of Turkey said the grain deal could form the basis for peace talks between Ukraine and Russia. But few share the enthusiasm. President Zelensky said negotiations can only start after Russia leaves territory it invaded.
Their talks in Lviv were overshadowed by the tensions around the Zaporizhzhia nuclear power plant, hundreds of miles away.
They all expressed concern that the military activity around the station could result in a catastrophe. There’s hope diplomacy can solve this crisis too, although there are no signs of it yet.
Image source, ReutersEmployees of Zaporizhzhia nuclear power plant have said they are "powerless" in the face of "human irresponsibility and madness".
They've warned of a potential nuclear catastrophe at the facility, saying in the past two weeks it has become "the target of continuous military attacks".
"Artillery strikes are becoming more and more powerful and dangerous every time," they say.
The plant, the largest in Europe, has been occupied by Russian forces since March, though its Ukrainian staff have continued with daily operations. The message from the workers does not name either Russia or Ukraine, which have both blamed each other for shelling near the plant.
Some of the facility's 10,000 staff are being injured or killed at work, they add, in the appeal published on the Telegram messaging app, external.
"Stop and think!... What is happening is horrific and beyond common sense and morality," they write, warning that an accident could be worse than the nuclear disasters at Chernobyl and Fukushima.
"We know how to professionally manage a nuclear reaction, but are powerless before human irresponsibility and madness," they say.
Image source, Getty ImagesThe Zaporizhzhia nuclear power plant has been occupied by Russian forces since March
Ukraine's main intelligence agency has accused Russia of planning to stage a "provocation" at the Zaporizhzhia power plant.
Moscow wants to "raise the stakes", a Telegram post from the agency alleges. It claims that Russia is planning a terrorist attack at the site which will be blamed on Kyiv.
The plant, the largest in Europe, has been under Russian control since March.
The post says that representatives from the Rosatom, the Russian state nuclear corporation, had suddenly left the site.
Earlier, Russia made its own accusation that Kyiv was plotting an incident which it could blame on Moscow.
Hugo Bachega
BBC News, Kyiv
Image source, ReutersWe've been hearing Turkey's President Recep Erodgan and UN chief Antonio Guterres warn about the dangers of the situation at the Zaporizhzhia nuclear plant.
Ukrainian President Volodymyr Zelensky is accusing Russia of “nuclear blackmail” over tensions at the complex, Europe’s largest.
Officials here claim Russia is creating this crisis to try to force Ukraine and other countries to comply with their conditions.
Ukraine says Russia has deployed around 500 forces to the complex, who are using it as a shield to launch attacks against Ukrainian towns.
Russia, on the other hand, denies the accusations, and says its troops are, in fact, protecting the plant.
Image source, ReutersFor days, Russia and Ukraine have accused each other of shelling near the site, fuelling fears of a nuclear catastrophe. It’s hard to independently verify the allegations, as the plant is off limits.
The facility has been under Russian occupation since early March, although Ukrainian technicians still operate it.
They’re working under pressure, and there are claims some have been detained, tortured and beaten.
Image source, Getty ImagesUN chief Antonio Guterres says damage to the Russian-occupied Zaporizhzhia nuclear power plant in Ukraine would be "suicide".
Speaking to reporters after talks in Lviv, Guterres says he was "gravely concerned" about the situation at the plant and said it had to be demilitarised.
He says: "We must tell it like it is - any potential damage to Zaporizhzhia is suicide."
Guterres adds the facility must not be used as part of "any military operation" and that "agreement is urgently needed to re-establish Zaporizhzhia's purely civilian infrastructure and to ensure the safety of the area".
Image source, Turkish Presidential Press OfficeTurkey's President Recep Tayyip Erdogan has said the world doesn't want "another Chernobyl", warning of the possibility of a nuclear accident at Zaporizhzhia if conflict there continues.
He's been speaking at a press conference in Lviv, following talks with his Ukrainian counterpart Volodymyr Zelensky and UN chief Antonio Guterres.
Erdogan says the trio also discussed ways to end the war between Russia and Ukraine.
He says they discussed the exchange of prisoners of war between Ukraine and Russia, and that he would later raise the issue with Russian President Vladimir Putin.
Turkey has recently acted as a mediator between the two countries, including on the issue of unblocking grain exports from Ukraine's ports.
Will Vernon
BBC News, Moscow
Image source, Getty ImagesThe Russian defence ministry’s statement earlier today can be summarised in two words: Blame Ukraine.
During press briefing at the ministry’s imposing building in central Moscow, Lt-Gen Igor Kirillov, who is head of Russia’s radioactive, chemical and biological defence forces, gave a presentation in which he accused the Ukrainians of endangering the Zaporizhzhia nuclear plant, which Russian forces control.
He claimed the plant's back-up support systems had been damaged as a result of Ukrainian shelling, and that Kyiv was planning a provocation – an “industrial disaster” – at the power plant on Friday, the same day that UN Secretary General Guterres visits the Ukrainian port city of Odesa.
During his presentation, Lt-Gen Kirillov presented a slide that showed how radioactive material would spread over Germany, Poland and Slovakia in the event of an accident at the plant.
We see this kind of narrative almost daily in Russia, both in official statements and on state-controlled TV. Moscow says Ukraine is guilty of everything from shelling civilian areas and committing war crimes, to planning nuclear meltdowns.
At the same time, it fails to mention that it was Russia that invaded Ukraine and occupied its territory, and it is Russian troops that are accused of committing atrocities.
The latest warning is likely more distraction tactics by Moscow. By stressing the risks of a nuclear accident and decrying the alleged “crimes” of the Ukrainian government (as Moscow sees it), the authorities can draw the public’s attention away from the Russian army’s poor performance on the battlefield.
Russian forces have barely seized more than a handful of villages in Ukraine in the last month, whilst casualties are mounting.
Image source, ReutersUN Secretary General Antonio Guterres has urged Moscow and Kyiv to show a "spirit of compromise" and ensure the continued success of the grain deal that enabled the resumption of grain exports from Ukraine.
Speaking at a press conference after talks in Lviv with Ukraine and Turkey's leaders, Guterres tells reporters that 21 ships had departed from Ukrainian ports under the deal in less than a month, and 15 vessels had left Istanbul for Ukraine to load up with grain and other food supplies.
He adds: "But it is only the beginning. I urge all parties to ensure continued success.
"From day one, the parties have worked professionally and in good faith to keep the food flowing. I appeal for this to continue and for them to overcome all obstacles in a spirit of compromise and permanently settle all difficulties."
He also reiterated his plea for the demilitarisation of the nuclear power plant held by Russian forces in Zaporizhzhia, saying he was gravely concerned by the situation in and around it.
Russia has dismissed the proposal, claiming it would make the facility "more vulnerable".
Image source, Getty ImagesA Russian foreign ministry spokesperson has said that while a clash with the collective West is possible, a direct nuclear conflict with the US and Nato would not be in Russia's interests.
"Russia has never sabre-rattled weapons, especially nuclear weapons. But the events in Ukraine... clearly show that a clash with the collective West is quite real," Ivan Nechayev said, as reported by the Interfax news agency.
Moscow is "committed to the principle that there can be no winners in a nuclear war, and it should never be unleashed", he said.
"Russia, as a nuclear power, will continue to act as responsibly as possible. A direct clash with the US and Nato is not in our interests.
"Russian military doctrine allows a nuclear response only in response to aggression using weapons of mass destruction, or when the very existence of the state is threatened."
We're hearing more now from the talks between Ukrainian President Volodymyr Zelensky and UN chief Antonio Guterres.
Zelensky says the two leaders discussed grain, after exports from Ukraine resumed this month following a landmark deal brokered by the UN and Turkey.
Tonnes of grain had been stuck in Ukraine because of Russian blockades, leading to shortages and higher food prices in other countries.
"We agreed to continue the coordination of the grain initiative implementation. We also discussed the possible directions of its development," Zelensky says.
Image source, ReutersThis ship was loaded with grain for Ethiopia in the port of Yuzhne in the Odesa region on Sunday