Prime Minister Boris Johnson says he has been struck by the "continuing unity" of the G7 during Russia's invasion of Ukraine.

"There is no deal that President Zelensky can really do, so in those circumstances the G7, supporters of Ukraine around the world, have to continue to help the Ukrainians to rebuild their economy, to export their grain and to protect themselves," Johnson says.

He adds that the situation in the south east of the country remains "very difficult", but Ukraine has demonstrated an "incredible ability to push back and change the military position".

There are a number of challenges in getting Ukraine's grain out of the country - and potentially escorting grain shipments through the Black Sea, says naval analyst Dr Sidarth Kaushal.

Those waters are currently highly dangerous for civilian shipping, Kaushal, of Royal United Services Institute, tells BBC Radio 4's Today programme.

This is because of naval mines laid at the start of the war, both by the Russians and also by Ukrainian forces. Also because of the activities of Russia's Black Sea fleet, which has carried out missile strikes on port terminals and damaged a number of ships in port.

To end the threat from the Black Sea fleet, at a minimum, "a prerequisite would be clearing channels through the minefields around Odesa" and for the Russians not to interfere with mine clearing, he says.

That would still leave some major challenges – for one thing, civilian shipping would require a "massive amount of insurance", something governments don't entirely control.

Russia has already hinted it might request the lifting of sanctions to help in the process.

Turkey's co-operation is also needed in this, given its control of the sea's straits and it being the other preponderant power in the Black Sea.

"It can be done, as to whether it will be done, that's a much more open question," he concludes.

Image source, Getty Images

Russia is believed to have defaulted on its debt for the first time since 1998 after missing a key deadline.

Russia has the money to make a $100m payment and is willing to pay, but sanctions made it impossible to get the sum to international creditors.

The Kremlin had been determined to avoid the default, which is a major blow to the nation's prestige.

The $100m interest payment was due on 27 May. Russia says the money was sent to Euroclear, a bank which would then distribute the payment to investors.

But that payment has been stuck there, according to Bloomberg News, external, and creditors have not received it.

Read more here

A BBC investigation has found evidence that occupying Russian forces have stolen thousands of tonnes of grain from Ukraine.

Documents show that the Russian-installed authorities have told farmers they're seizing their grain to ensure what they call "food security".

However, CCTV from one farm appears to show Russian soldiers looting.

Moscow denies any theft, but American officials have named nine ships believed to have transported the stolen grain from Crimea to other parts of the world.

It comes as the UN is warning of famine in Africa and the Middle East because of the disruption to supplies from Ukraine, one of the world’s biggest wheat producers.

Read the full investigation here.

Shelling in the Izyum region in eastern Ukraine over the past week suggests Russia is trying to regain momentum there, the UK's Ministry of Defence says.

The MoD says in its daily update that while Russia's operational focus remains on the Severodonetsk-Lysychansk pocket, it appears the northern Izium area is being targeted.

It says Ukrainian forces continue to hold the line in that sector and are making good use of forested terrain as part of their defence.

It comes as Russia made a strategic breakthrough on Saturday in Severodonetsk after weeks of fierce battles, reducing much of the eastern industrial city to rubble.

Russia's campaign in the weeks ahead is highly likely to rely on reserve forces, the MoD says, several of which have "almost certainly" already begun being fielded.

These include part-time, volunteer reservists likely to be deployed for security tasks, as well as veterans who served in the military within the past five years, it adds.

More than 100 bodies have been found under the debris of a residential building in Mariupol, the mayor's advisor says.

Petro Andryushchenko says in a post on Telegram there are no plans by Russian forces to retrieve and bury the bodies after the housing block was hit by an air strike.

The port city fell to the Russians last month, having been all but destroyed by weeks of shelling.

Image source, .

Image source, PA Media

As we've been reporting, G7 leaders have convened in Germany for a three-day summit in Bavaria, with the war in Ukraine top of the agenda.

On the opening day yesterday, they stressed their unified position in supporting Ukraine and set out plans to mobilise hundreds of billions of dollars in infrastructure investment for the developing world.

US President Joe Biden said the initiative would show the concrete benefit of partnering with democracies.

EU Commission President Ursula von der Leyen said it would help poor countries deal with the twin economic shocks of the Covid pandemic and the war in Ukraine.

Many developing countries blame Western sanctions - as well as Russia's invasion - for the rising costs of gas and oil, and the massive shortage of wheat and fertiliser.

Chancellor Olaf Scholz of Germany stressed the importance of investment in low carbon energy - in response to what he called Russia's use of energy as a weapon.

James Landale
Diplomatic correspondent

This summit has a broad agenda, from tackling climate change to helping poorer countries with infrastructure. But Ukraine continues to dominate.

The G7 leaders are expected to offer more support and further sanctions on Russia.

But even Boris Johnson - one of Volodymyr Zelensky's most vocal supporters - admits defending Ukraine's sovereignty has tough consequences for the rest of the world, particularly the rising costs of food and energy.

That's why the leaders of South Africa, Indonesia, India and Senegal have been invited to join the summit today, to discuss what more can be done to tackle global inflation. One idea being looked at is a cap on the price of Russian oil.

Image source, Getty Images

Ukrainian President Volodymyr Zelensky has renewed calls for weapons ahead of his address to the G7 nations today.

Zelensky is expected to urge the seven wealthy nations to send more heavy arms to his country and to impose tougher sanctions on Russia.

Speaking in his daily late-night speech, he said any delay in the provision of weapons to Ukraine was "an invitation for Russia to strike again and again".

"We need a powerful air defence - modern, fully effective," he said.

"We talk about this every day with our partners. There are already some agreements. And partners need to move faster if they are really partners, not observers.

"Delays in the transfer of weapons to our state, any restrictions are actually an invitation for Russia to strike again and again.

"The occupiers - these terrorists - must be beaten with all our might so that they do not think they can put pressure and outplay someone."

Good morning from London as we resume our coverage of the conflict in Ukraine. Here are the latest developments:

• Ukrainian President Volodymyr Zelensky is due to address G7 leaders at their summit in Germany later
• A BBC investigation has found evidence that occupying Russian forces have stolen thousands of tonnes of Ukrainian grain
• Russia is said to have defaulted on its overseas debt for the first time in more than a century after missing a Sunday deadline, according to reports

• Ukraine has renewed pleas for Western countries to provide it with modern air defence systems to protect its cities from Russian attack after a weekend of heavy missile strikes - including the most sustained barrage on the capital, Kyiv, in months
• President Zelensky said in his nightly address on Sunday that a delay in providing weapons would be "an invitation for Russia to strike again and again"

Image source, EPA

We're pausing our coverage of the war in Ukraine now. Here's a reminder of the main developments today.

Russia has launched a number of missile attacks on Ukraine - including the heaviest sustained targeting of the capital Kyiv for months. The city was hit by at least 14 Russian missiles early in the morning, with an apartment block building destroyed, leaving one person dead and several wounded, including a seven-year-old girl who has undergone surgery.

One person died and five were injured when Russian missiles hit the central Cherkasy region, local authorities said, and there were also strikes in the Kharkiv and Sumy regions.

Kyiv Mayor Vitaliy Klitschko said the attacks were Moscow's attempt to "intimidate" Ukraine, ahead of a meeting of G7 leaders, which has opened today, and a Nato summit which follows it.

And the war has been the main topic of discussions at the G7 summit in Bavaria. The meeting's host, German Chancellor Olaf Scholz, said unity over Ukraine was the G7's clear message to Russian President Vladimir Putin. Leaders are expected to promise further military support for Kyiv and impose more sanctions on Moscow.

Image source, EPA

Today's coverage has been brought to you by Nathan Williams, James Clarke, Sophie Williams and Yaroslav Lukov.

Sophie Williams
Reporting from Kyiv

Air raid sirens are going off again here in the Ukrainian capital Kyiv.

According to a number of tracking maps, most of the country is under alert.

It comes after Russia launched a number of missile attacks on the country earlier this morning.

The attack on Kyiv today was the first time the capital has been targeted in three weeks.

Imogen Foulkes
Reporting from Geneva

The Red Cross has been helping families find their loved ones lost in war since 1859, when its founder Henri Dunant came across soldiers dying after the battle of Solferino in northern Italy and learned one of them was concerned his mother would not know what had happened to him.

Now, the Red Cross is trying to bring news to worried mothers in Ukraine and Russia. It says it has registered hundreds of prisoners among those who surrendered at the Azovstal steel plant in the southern Ukrainian port city of Mariupol in May.

Red Cross officials will not disclose exactly how many, but they are getting prisoner lists from both Russian and Ukrainian forces, and the numbers are believed to run into the thousands.

Equally high are the numbers of families desperate for news. In the Central Tracing Agency's mailroom, up to 400 emails are coming in each day. The agency has already informed almost 1,800 families about the whereabouts of missing loved ones.

Zhanna is on the phone in the agency's offices in Switzerland, talking to a young Ukrainian woman whose husband was taken prisoner at the steel plant.

"She asked me: 'Can I leave with you some personal information?'" says Zhanna. "I said yes, with pleasure: 'If the Red Cross go and see my husband, could you please tell him that today I gave birth to our child, at 12:45, 3 kilos, 6 grams.'"

Read more about the work of the agency - and the stories of those needing its help - from Imogen here.

Russia's invasion of Ukraine has given the G7 a new lease of life, a Cambridge University international politics and history lecturer has told the BBC.

"It's given them a political focus they haven't had in a while," says Dr Tristen Naylor, who is in Bavaria, where the G7 leaders are meeting.

"The club has met seven or eight times either online or in person since the invasion, this is very much their focus - has been over the past couple of months and it certainly will be here," he says.

"The order of the day will certainly be to demonstrate resolve, it will be to communicate to Ukraine, Russia and the rest of the world, that the G7 is united. They're not going to fracture on this, and they're going to see what sort of further support they can bring together for Ukraine, whether that's weapons, whether that's money - everything's on the table."

He says the G7 may have more influence over Ukraine than Nato, which holds a summit in Madrid later this week, because it can be more flexible.

"Nato cannot be seen to be directly escalating the conflict, so the range of policy options at their disposal as a military club is actually far more limited than it is for the G7," Naylor says.

"So I think this weekend is really critical for telling us about what direction western support for Ukraine will be in the coming weeks and months."

James Landale
Diplomatic correspondent

In recent weeks some in Europe have voiced different opinions about the war in Ukraine. But the G7 leaders meeting in Bavaria appear determined to put on a united front.

President Biden said Vladimir Putin had been counting on the G7 and the Nato alliance dividing. But we haven't and we're not going to, he said.

Boris Johnson admitted there was anxiety about the war. Western leaders had to be honest about that. But he insisted the G7 remained united.

At a meeting with President Macron of France, who talks often to President Putin, Johnson stressed that any attempt to settle the conflict now would only cause enduring instability.

The PM also told his Canadian counterpart, Justin Trudeau, that the conflict was on a knife-edge and the West had to tip the balance of the war in Ukraine's favour.

Image source, Reuters

As we reported earlier, a seven-year-old girl was injured in Kyiv when a Russian missile hit a nine-storey building in the Ukraine capital in the early hours of Sunday.

The girl was pulled from the rubble and taken to the city's main children's hospital, Ohmatdyt.

"The girl was conscious when she was admitted to the hospital," Ohmatdyt medics say, adding that she had "numerous wounds, bruises and abrasions".

She later underwent a surgery, and was now "in stable condition".

"Her life is not in danger," Ohmatdyt adds.

The US ambassador to Ukraine, Bridget Brink, says she is "appalled by reports today of Russian missile strikes on a residential building & kindergarten in central Kyiv".

"As the Kremlin continues its indiscriminate attacks on Ukrainian civilians, the US & our partners will pursue every avenue to ensure those responsible for atrocities are held accountable," the envoy tweets.

Earlier on Sunday, US president Joe Biden urged allies "to stay together" against Russia, as world leaders were gathering for a G7 summit in Munich, Germany.

The summit is expected to be dominated by Moscow's invasion of Ukraine and its far-reaching impact on food and energy supplies across the world.

Image source, Oleh Syniehugov/Kharkiv regional administration

Ukraine's north-eastern Kharkiv region has recently been under heavy Russian bombardment, that left a number of people dead.

Regional head Oleh Syniehubov says the region was shelled again overnight.

Since the start of the Russian invasion on 24 February, Russian troops have destroyed 4,019 residential homes, 97 medical facilities and 427 educational institutions, the regional head reminds.

He posted images of a bombed out sports facility in the regional capital Kharkiv, saying the complex had been used by thousands of children and students before the war.

"Not a single day went by without the occupiers striking the Kharkiv region! So, we can't afford to relax, each time you ignore air sirens can cost your life!" Syniehubov warns.

It's more difficult than it may seem for Russia to make advances in Ukraine - partly due to Russia's own successes. That's according to Dr Natasha Kuhrt, of the War Studies Department at King's College London.

"Ukraine now has a much shorter line to defend because it's been giving up ground in the east, that means Ukraine is better able to defend against Russia," Dr Kuhrt, a lecturer in international peace and security, tells BBC Radio 5 Live.

"And of course Ukraine, despite giving up ground in the east, is actually advancing in the south still."

Image source, .

Kuhrt says it's obvious Russia underestimated Ukraine's abilities to resist but so did the rest of the world.

"Even if Russia is being pushed back it is not going to give up any time soon - it can still cause a huge amount of wanton destruction, which is Russia modus operandi, which we've seen before In Syria and Chechnya.

"In the long run - and we don't know how long that run will be - Russia may not be victorious on the battlefield. But at the same time we've got a long haul and Russia will pound Ukraine with as much artillery and so on as it can."

Image source, Reuters

If you're just joining us - here's a quick recap on what's been happening so far on Sunday in Ukraine:

• The capital Kyiv was hit by at least 14 Russian missiles early in the morning - in the most sustained such barrage in months, local officials said
• At least one person was killed and several injured after a nine-storey house was hit in the city
• Among those wounded was a seven-year-old girl, who was pulled from the rubble
• One of the Russian missiles hit an empty kindergarten playground
• Kyiv Mayor Vilaliy Klitschko said the attacks were Moscow's attempt to "intimidate" Ukraine
• One person died and five were injured when Russian missiles hit the central Cherkasy region, local authorities said
• One person was injured in mortar shelling in the north-eastern Sumy region
• There were also overnight strikes in the nearby Kharkiv region, where officials say more than 4,000 houses have been destroyed since the war started
• Russian Defence Minister Sergei Shoigu inspected troops taking part in what Moscow describes as a "special military operation", state media say
• No further details were given, but Shoigu is believed to have visited a location in the Russian-occupied eastern Ukraine