We'll be pausing our live coverage shortly but before we do here are some of the day's key developments:

• The consequences for the world of Russia's invasion of Ukraine are worsening and the "impact on food security, energy and finance" is "severe", according UN chief Antonio Guterres
• Talks between Russia and Turkey to allow grain exports to resume from Ukraine's ports have ended without a solution
• Ukraine has dismissed "empty" assurances from Russia's foreign minister that Moscow won't take advantage of the situation if Kyiv allows grain shipments to leave via the Black Sea
• The battle for control of the key eastern city of Severodonetsk continues, as Russia tries to capture all of the Luhansk region. Regional governor, Serhiy Haidai, says Ukrainian fighters now hold only the city's outskirts
• Ukraine's President Volodymyr Zelensky says defenders in Severodonetsk are inflicting losses on Russian troops during what he calls "a very fierce and very difficult battle"
• More than 1,000 Ukrainian soldiers captured in Mariupol have reportedly been transferred to Russia, according to Itar-Tass, a state owned Russian news agency

As the war in Ukraine grinds on, we've received new pictures showing Ukrainian soldiers near the frontlines of Izyum, south of Kharkiv.

Image source, EPA

Image source, EPA

Image source, EPA

Image source, Getty Images

Global banking experts believe Russia's economy will shrink 15% by the end of the year - and a further 3% in 2023 - due to Western sanctions, a mass exodus of companies and a collapse in exports.

The figures could be even worse if Europe fully weans itself off Russian energy, the Institute of International Finance (IIF) warned.

In a report about the effects of war on Russia's finances, the IFF said measures imposed on Moscow by the UK, EU and US would only expand and tighten in the coming months.

They've already triggered the "full disintegration of 30 years of investment" for Russia, Elina Ribakova, the IIF's deputy chief economist, said. She added it was hard to put a figure on "ripping apart 15 years of value chains".

Two Britons and a Moroccan man who were captured while fighting for Ukraine have pleaded partially guilty in a court in the so-called Donetsk People's Republic (DPR), according to Russian state media.

Aiden Aslin, 28, from Nottinghamshire, Shaun Pinner, 48, from Bedfordshire and Moroccan national Saaudun Brahim were seen in a video of the court proceedings published by news agency Ria Novosti.

In the video, Aslin appeared to plead guilty to a lesser charge involving weapons and explosives.

He was seen standing in the cage leafing through several pages of legal documents as the charge was read out.

The head of the DPR, Denis Pushilin, said on Monday that the death penalty could not be ruled out for the men.

Ukrainian President Volodymyr Zelensky says defenders in the city of Severodonetsk were inflicting major losses on Russian troops during what he called "a very fierce and very difficult battle".

"In many respects, the fate of the Donbas is being decided there," he said in an online address reported by the Reuters news agency.

As we've been reporting, most of Severodonetsk is under Russian control and Ukrainian fighters now hold only the city's outskirts, according to the regional governor.

Russia is sending grain from Ukraine overseas, Russian-appointed officials in occupied southern Ukraine say.

The claim - which the BBC has not been able to verify - comes as Ukrainian officials accuse Russia of stealing about 600,000 tonnes of its grain and exporting some of it.

Russia denies it is stealing grain.

Accessing Ukraine's stockpiled grain has become urgent internationally: millions of tonnes are exported annually to Africa and the Middle East.

But it cannot be shipped now because Russia's navy is blockading Ukraine's Black Sea ports.

And Russia says Ukraine must de-mine waters off the Black Sea Coast for corridors to export the grain to become operational.

Read the full story here.

We reported earlier on a case raised in the House of Commons of a 13-year-old Ukrainian girl refused a visa to enter the UK because she was travelling with her sister, rather than her parents.

Labour MP Tulip Siddiq said the older sister, 18, was now in London but her sister had returned to her Ukrainian home in a town she said was under siege. She asked the prime minister if it was right to send a child back to a war zone.

We asked the government to comment and the Department for Levelling Up, Housing and Communities, which shares responsibilities for issuing visas to Ukrainian refugees with the Home Office, referred us back to Boris Johnson's reply to the MP.

The PM said he understood her indignation but said he knew the home secretary would look into the case and highlighted that the UK had processed 120,000 visas for Ukrainians, which was "creditable".

The department also said only under-18s who are reuniting with a parent or legal guardian in the UK are currently eligible for the Homes for Ukraine scheme, but it was keeping the schemes under constant review and did take the safety of children "extremely seriously".

The city of Lysychansk is completely under control of Ukrainian troops after being attacked by Russian forces for more than a week, according to Luhansk regional governor, Serhiy Haidai.

He said Russia continues to "chaotically" and "powerfully" shell the city, causing huge destruction to housing.

Writing on Telegram, Haidai says there is "no threat" of encirclement of Ukrainian troops in Luhansk region, but Russian forces temporarily control 90% of the region, he adds.

Russia has been determined to take control of Severodonetsk and its neighbouring city Lysychansk, as part of a plan to control the wider Donbas region and eventually the whole of eastern Ukraine.

Image source, .

Ukraine may have a grain storage capacity deficit of 10-15 million tonnes by the end of autumn but the government is trying to resolve the problem, the country's Deputy Agricultural Minister, Markiyan Dmytrasevych said.

Ukraine had 85 million tonnes worth of grain storage capacity before Russia began its invasion on 24 February.

However, Ukraine now only has access to 60 million tonnes worth of storage capacity because of destroyed infrastructure and Russia's occupation of the country.

Russia's invasion of Ukraine could soon cause a global food crisis that may last for years, the UN has warned.

As we've been reporting through much of today, the blocking of Ukraine's main ports on the Black Sea during the war has severely impacted food supply chains around the world.

The country is a major exporter of wheat, but now millions of tonnes of grain are stuck - hitting the countries that can least afford it.

The West has accused the Russian military of holding food supplies hostage for millions around the world.

Russia denies it is weaponising food supplies, claiming Ukraine's attempts to mine the Black Sea and sanctions are to blame.

The BBC's Ros Atkins explains the situation in this video, first published two weeks ago.

Image source, Reuters

The food crisis gathering pace since Ukraine was invaded could last years rather than months if decisive action isn't taken, according to the director general of the World Trade Organization.

Dr Ngozi Okonjo-Iweala tells the BBC's global trade correspondent Dharshini David she fears the grain shortages caused by the war will result in "a dire situation worldwide".

Ukraine contributes 42% of the sunflower oil exported around the world, 16% of the maize, 10% of the barley and 9% of the wheat.

"If we are not able to evacuate grains in Ukraine now and then they have a harvest coming up in July with a similar quantity going to waste, then you can see that this will work its way through for the next couple of years - that will be really, really disastrous for certain parts of the world," Okonjo-Iweala says.

She says Africa will be particularly badly hit because many African countries import food or fertilisers from the Black Sea region.

More now from our interview with Valaray - the 16-year-old who was photographed in a graduation dress in her shelled school - who says the situation in Kharkiv remains very scary.

The city in north-east Ukraine was bombed overnight.

"It was very loud last night. It's very scary in Kharkiv since the first day and it's very dangerous and scary every day," she says.

"Half of my class has moved abroad, some civilians were living underground but now a sort of normal life is starting to return."

She says the idea to return to the school had come from her classmates and they were helped to do so by the Ukrainian military.

"As for my photograph of me I wanted to show the contrast between my school and me. It describes the situation in the country," she adds.

The UN chief says he has asked colleagues to help find "a package deal that allows for the safe and secure export of Ukrainian-produced food through the Black Sea, and unimpeded access to global markets for Russian food and fertilizers".

"This deal is essential for hundreds of millions of people in developing countries, including in sub-Saharan Africa," Antonio Guterres adds.

He was speaking at the presentation of a UN report into the repercussions of the conflict which estimates that 94 countries - the home to about 1.6bn people - are "severely exposed to at least one dimension of the crisis and unable to cope with it".

"Out of the 1.6bn, 1.2bn or three quarters live in 'perfect-storm' countries that are severely exposed and vulnerable to all three dimensions of finance, food, and energy, simultaneously," it adds.

Image source, Reuters

The consequences for the world of Russia's invasion of Ukraine are worsening, UN chief Antonio Guterres says, affecting 1.6 billion people.

"The war's impact on food security, energy and finance is systemic, severe, and speeding up," the UN Secretary General says, quoted by the AFP agency, as he presents the UN's second report into the repercussions of the conflict.

The war "threatens to unleash an unprecedented wave of hunger and misery, leaving social and economic chaos in its wake", Guterres says.

While this year's crisis looks to be about a lack of access to food, next year's might be about a lack of food itself, he warns.

"There is only one way to stop this gathering storm - the Russian invasion of Ukraine must end".

Image source, Getty Images

A 16-year-old who was photographed in a graduation dress at her high school months after it was destroyed by Russian shelling says she never thought her picture would be seen around the world.

"It was not about me. It was more about bringing attention to the situation," Valaray tells the BBC World News.

"We are proud of our heroes and our armed forces of Ukraine. We believe we will win because kindness will always win over evil," she adds.

Her aunt Anna Episheva posted the photo on social media, in which she said Valaray and her friends "bought dresses and were looking forward to this day".

"Then Russians came. Her school was directly hit and destroyed. Today she came back to what is left of her school and her plans," Episheva said.

Image source, Getty Images

Russian-appointed officials in occupied southern Ukraine say Russia is sending grain from occupied areas to the Middle East via Crimea.

Yevgeny Balitsky said trains carrying grain had left Zaporizhzhia region, where he runs Russian-held areas.

He told Russian state TV “the main contracts are being concluded with Turkey”.

Russia annexed Ukraine’s Crimea peninsula in 2014. The grain is to be shipped from there, Balitsky said, without specifying quantities or type.

"The first trains have already gone through Crimea, in the direction of the Middle East," he said.

A Russian official in Crimea, Oleg Kryuchkov, said the first train carrying grain had arrived from Melitopol, a city in Zaporizhzhia.

Ukraine accuses Russia of having stolen about 600,000 tonnes of grain and exported some of it.

The BBC has been unable to verify details of the reported shipments.

Countries in the Middle East are heavily dependent on imports of grain from Ukraine and Russia, especially wheat.

Ukrainian forces have been pushed back to the “outskirts” of Severodonetsk following Russian bombardment of the city, according to the region’s governor Serhiy Haidai.

He told the RBC-Ukraine media outlet Ukrainian special forces launched a counteroffensive days ago and cleared almost half of the city, but said it made no sense for them to stay when Russia started levelling the area with shelling and air strikes.

Haidai said: "Our [forces] now again control only the outskirts of the city. But the fighting is still going on, our [forces] are defending Severodonetsk,” adding “it is impossible to say the Russians completely control the city".

Image source, .

Image source, Reuters

Ukraine has criticised former German chancellor Angela Merkel after she said she had "nothing to apologise for" over her response to Russia's annexation of Crimea from Ukraine in 2014.

Merkel, who left office six months ago, said on Tuesday that Europe and Russia were neighbours that could not ignore each other. "We have to find a way to co-exist despite all our differences," she said.

But Ukrainian presidential adviser Mykhaylo Podolyak said Merkel had "shoved" Europe towards greater dependency on Russian energy supplies.

"If Chancellor Merkel always knew that Russia was planning a war and Putin's goal is to destroy the EU, then why would [Germany] build the Nord Stream 2," he wrote on Twitter, external.

Merkel's successor Olaf Scholz suspended the gas pipeline project in February after the invasion. You can read more about it here.

As we've been reporting, reduced grain shipments from Ukraine have fast become one of the biggest crises caused by the war.

And Nikolay Gorbachov, president of the Ukrainian Grain Association, has now rejected a suggestion to use western Ukraine and Europe as an alternative shipping route to the Black Sea. It's "impossible", he told BBC World News.

Ukraine exports around "six to seven million tonnes of grain and oil seeds per month [via its Black Sea ports]," he said, but through the "Western border we can get across one, at best one-and-a-half million".

Europe does not have the infrastructure to deal with Ukraine's volume of grain exports, he added.

On talks today in Ankara, between Russian Foreign Minister Sergei Lavrov and his Turkish counterpart Mevlut Cavusoglu, Gorbachov said any resolution to this issue would need to involve Ukraine.

Image source, House of Commons

A 13-year-old girl was sent back to her besieged Ukrainian home town after her visa application was refused by the UK, an MP has told the House of Commons.

The girl's 18-year-old sister is now in London. However, the younger sibling has returned to Ukraine, after her visa was turned down because she was not travelling with her parents, Labour's Tulip Siddiq said at Prime Minister's Questions.

Siddiq said one of her constituents was trying to sponsor the two sisters to come to the UK.

"These two sisters were housed in dangerous temporary accommodation in Montenegro for several weeks while the UK Home Office refused to process the application of the younger sister because she is 13 and travelling without her parents, even though she had her 18-year-old sister with her," she said.

"Can I ask the prime minister, can he tell me hand on heart, does he think sending vulnerable children back to a war zone is the right policy?"

Boris Johnson said he understood the MP's "indignation" and he knew the home secretary would be looking into it. "I do think the record of this country in processing, so far I think, well over 120,000 visas for Ukrainians is very creditable," he added.

We've asked the Home Office for a comment on the sisters' case.

You can read more on the process of Ukrainians seeking visas for the UK here.