Michael Race
Business reporter, BBC News

Image source, Getty Images

Away from the conflict on the ground in Ukraine itself, one Russian oligarch has posted on social media about the country's "massacre" in Ukraine and called for an end to the "crazy war".

Oleg Tinkov wrote in a profanity-littered Instagram post that he did not see "any beneficiary" of the conflict.

Mr Tinkov is one of Russia's most high-profile entrepreneurs and founded the global online finance firm Tinkoff Bank and owned the cycling team Tinkoff-Saxo.

He is one of the most high profile Russians to publicly condemn President Vladimir Putin's actions.

Two of the country's other prominent oligarchs, Mikhail Fridman and Oleg Deripaska, have made sperate calls for peace but stopped short of direct criticism.

Mr Fridman, a billionaire banker, has said any personal remarks could be a risk not just to himself but also staff and colleagues.

Mr Tinkov said "90%" of his country's people were against the war and added "morons in any country are 10%".

Read more here.

Here's what we know about the layout of the Azovstal steel plant in the southern port city of Mariupol, where Ukrainian troops and civilians are sheltering.

Thousands of people are inside the sprawling complex of tunnels and workshops which Russia has been attacking consistently. However, the Ukrainians refuse to surrender.

Troops have pleaded for international assistance for the 500 wounded soldiers and hundreds of women and children who are hiding in the steel plant.

Image source, .

Image source, Reuters

A former resident of Mariupol says people are nervous about leaving the embattled city because they fear the situation is just as bad in other parts of Ukraine.

"They think that what is happening in Mariupol [is] happening everywhere," Roman Skyliarov told the BBC World Service's Newshour programme.

"They don't have full information at all because they don't have internet."

Roman says he fled the southern city himself but knows others who are keen to stay - who include young people as well as his grandmother.

Efforts to try to evacuate civilians from the city continue, despite repeated previous failures to arrange organised convoys of buses.

Image source, Getty Images

Russian forces claim control of most of the southern port city – with the final Ukrainian defenders holed-up in the Azovstal steel plant. Here's a round-up of the latest developments:

• The 11:00 GMT (12:00 BST) deadline issued by Russia for the last Ukrainian forces in Mariupol to lay down their weapons has passed - with no sign that the defenders have surrendered
• A marine commander in the Azovsta steelworks complex had said his troops will not surrender, but pleaded for international assistance
• Mariupol's mayor hopes to evacuate 6,000 people today following a preliminary agreement with Russia, but about 100,000 people remain in the city
• Vadim Boychenko announced that evacuation corridors between Mariupol and Zaporizhzhia would be opening from 14:00 local time (11:00 GMT)
• He said that residents will be able to board buses from the city's Taganrogskaya Street and they will also stop near the Azovstal steel plant where Ukrainian soldiers are sheltering, and Shevchenko Boulevard
• But the city's deputy mayor says it's too early to tell if the agreed humanitarian corridor will be successful

Image source, REUTERS/Alexander Ermochenko

It’s too early to tell if the humanitarian corridor agreed to evacuate civilians from Mariupol will be successful, the cities Deputy Mayor Sergei Orlov tells the BBC.

He says Ukraine is ready and waiting with the buses to evacuate people in Ukrainian controlled territory but the city is “totally without electricity - no mobile phones" so it’s very hard to make people aware of the evacuation efforts.

Russia hasn't provided confirmation that they have let their troops know widely internally that they are planning to evacuate civilians, “all we received is the possibility”, Orlov says.

He says he does not trust the Russians to make a safe passage for civilians but “who knows, maybe this will be the first time such a corridor is set up”.

Around 90% of the buildings in Mariupol have been damaged by shelling and 40-45% of the cities infrastructure is totally destroyed and cannot be repaired, he adds.

He says he is "absolutely sure Ukrainian soldiers won’t give up" adding that there are hundreds of families living in the area around the Azovstal steel plant who are suffering from continuous air strikes and shelling.

Image source, Reuters

Russia has warned Sweden and Finland via bilateral diplomatic channels about the consequences of joining Nato, Foreign Ministry spokeswoman Maria Zakharova has said.

"We have issued all our warnings both publicly and through bilateral channels," Zakharova told broadcaster, Russia-24.

"They [Sweden and Finland] know about it, they will have nothing to be surprised about, they were informed about everything, what it will lead to."

Finland's parliament will open a debate today on whether to seek Nato membership, after Russia's invasion of Ukraine sparked a surge in political and public support for joining the military alliance.

Despite Russia warning of a nuclear build-up in the Baltic should Finland and neighbouring Sweden join the military alliance, Finland's prime minister said that her country would now decide quickly on whether to apply for membership.

Sweden is also discussing whether to submit a membership bid following Russia's invasion.

Image source, Reuters

The Azovstal Iron and Steel Works - a massive, four square-mile plant in the south-east of Mariupol - has become the last redoubt of Ukrainian resistance in the city.

Built in 1933, it was once one of the largest metallurgical factories in Europe, pumping out more than four million tons of crude steel every year and marked Mariupol out as an outlier in the Donbas region, which has traditionally relied on coal to drive its economy.

It is historically intertwined with Ukraine's conflicts, occupied by the Nazis in War War Two and by pro-Russian separatists in 2014.

But now, as Russian forces have advanced slowly into the heart of Mariupol, the sprawling complex has become home to thousands of Ukrainian soldiers, including fighters from the Azov battalion - a controversial national guard unit with links to the far right.

The site is a sprawling mass of tunnels and workshops and provides a natural advantage to defenders.

Yan Gagin, an official with the separatist Donetsk People's Republic, complained to Russian state news network RIA Novosti over the weekend that there is there is "basically another city" beneath the plant.

Russia has been bombarding the factory with artillery and air raids. Moscow has issued two demands for the Ukrainian troops there to surrender.

But an advisor to Ukrainian President Volodymyr Zelesnky said Russia is targeting the defenders with bunker busters, colossal bombs designed to penetrate thick armour and kill targets underground.

Image source, EPA

German Foreign Minister Annalena Baerbock has said Berlin has chosen not to reveal full details about the weapons it has sent to Ukraine.

Speaking after a meeting with her Latvian counterpart in Riga, Baerbock said "we have delivered anti-tank missiles, Stingers and other things that we have never spoken about publicly so these deliveries could happen quickly".

Baerbock added that her country would help Ukrainian forces maintain advanced weapons systems it has received from Germany and its allies as well as training soldiers to use them.

Ukraine has been urging its allies to provide additional military support after Russian forces launched a new offensive in the Donbas region.

The UK prime minister has been speaking about Aiden Aslin – a British fighter captured in Mariupol (see previous post).

During Prime Minister's Questions, Aslin’s local MP references footage of the 28-year-old shown on Russian television recently, and asks Boris Johnson if he agrees it breached the Geneva Convention, external.

The convention says prisoners of war must be treated humanely and it prohibits humiliating and degrading treatment.

Johnson doesn’t directly answer the question, but urges the Russian state to treat Aslin "humanely and compassionately".

He adds that while UK officials "actively dissuade" people from going to fight in Ukraine, Aslin had been serving in Ukraine’s armed forces for some time and his situation was "very different from that of a mercenary".

Read the latest on Aslin’s case here.

Image source, Facebook

One of the fighters captured in the besieged city of Mariupol is Aiden Aslin, 28, who is originally from the UK, but has dual Ukrainian citizenship and had been living there with his girlfriend.

Aslin had been defending the city with the Ukrainian marines before he became a prisoner of war.

His family have spoken out this morning after footage of him was shown on Russian TV.

In a statement via their MP on Twitter, external, they said: "Aiden was making plans for his future outside the military, but like all Ukrainians, his life was turned upside down by Putin's barbarous invasion.

His family said it was "deeply distressing" to see him looking bruised and swollen.

Read more here.

Mariupol mayor Vadim Boychenko earlier announced that evacuation corridors between Mariupol and Zaporizhzhia would be opening from 14:00 local time (11:00 GMT).

Boychenko posted that residents will be able to board buses from the city's Taganrogskaya Street and they will also stop near the Azovstal steel plant where Ukrainian soldiers are sheltering, and Shevchenko Boulevard.

Boychenko said "during these long and incredibly difficult days, you survived in inhumane conditions".

He added: "You were in an information vacuum, without access to any information".

Ukrainian Deputy Prime Minister Iryna Vereshchuk said the evacuation plan would involve a humanitarian corridor for women, children and the elderly.

The 11:00 GMT (12:00 BST) deadline issued by Russia for Ukrainian forces in Mariupol to lay down their weapons has passed - with no sign that the defenders have surrendered.

Although the besieged port city is surrounded by Russian forces, it hasn't fallen yet.

But a marine commander sheltering in Azovstal steel plant - the last Ukrainian stronghold in the city - said in a video that it is possible that they have "days or hours left".

Maj Serhiy Volyna said: "This is our last address to the world. It may be our last one ever."

He said his troops won't surrender, but he pleaded for international support. Maj Volyna added that 500 wounded soldiers and hundreds of women and children were sheltering alongside them.

Ukrainian Deputy Prime Minister Iryna Vereshchuk said it wants to evacuate civilians through a humanitarian corridor for women, children and the elderly. But there's been no word yet from the Kremlin on this.

Image source, Reuters

In Mariupol

• Russia has given the city's Ukrainian forces, holed up in a steelworks plant, a fresh ultimatum to lay down their weapons by 11:00 GMT
• A marine commander in the steelworks complex - the city's last Ukrainian stronghold - said his troops would not surrender, but pleaded for international assistance
• In a video, Maj Serhiy Volyna said 500 wounded soldiers and hundreds of women and children were sheltering alongside them
• Mariupol's mayor hopes to evacuate 6,000 people today in a preliminary agreement with Russia, but about 100,000 people remain in the city
• The UK Ministry of Defence accused Russia of "indiscriminate attacks" there

Elsewhere

• Russia's invasion is focused on the broader east of Ukraine, with both sides locked in combat along a 300-mile (480km) front line
• Russia's Ministry of Defence claims its forces have hit 1,053 Ukrainian military facilities overnight - the BBC can't verify this

• Ukraine also claims to have sprung counter-attacks retaking the town of Maryinka, near Donetsk
• The city of Izyum, a former tourist destination on the northern edge of Ukraine's Donbas, is seeing fierce fighting. Those who have managed to flee told the BBC it's on the edge of a humanitarian catastrophe

The number of Ukrainians to have fled abroad since Russia invaded on 24 February has now exceeded five million, the UN Refugee Agency (UNHCR) says.

Image source, .

The Azovstal Iron and Steel Works - a massive, four square-mile plant - has become the last bastion of Ukrainian resistance in Mariupol.

A marine commander in the stronghold issued a video message in the early hours of Wednesday morning saying his men might have only hours left.

Maj Serhiy Volyna said his troops would not surrender, but he pleaded for international assistance for the 500 wounded soldiers and hundreds of women and children he said were hiding with them at the steel plant.

Major Volyna is a commander of the 36th Marine Brigade.

Last week Russia said that 1,026 soldiers from that unit, including 162 officers, had surrendered in Mariupol.

Britons Aiden Aslin and Shaun Pinner, who had been defending Mariupol and were captured by Russian forces last week, were members of the brigade.

The other unit in the steelworks is the Azov Brigade, named after the Sea of Azov which links Mariupol to the rest of the Black Sea.

Azov is a militia linked to far-right nationalists which was later incorporated into the Ukrainian National Guard. Their numbers were estimated at around 900.

The marines teamed up with the Azov in Mariupol last week. It's unclear how many Ukrainian troops are left in the plant.

On Tuesday, Azov posted on Telegram: "We will fight, we will use every cartridge we have left, but we call on the homeland to save civilians, the wounded and take away the bodies."

Image source, Reuters

Ukrainian forces in Mariupol have successfully tied down thousands of Russian soldiers who otherwise would’ve been redeployed northwards for the main battle in Donbas, according to Professor Malcolm Chalmers, Deputy Director General of the Royal United Services Institute (Rusi).

"Defenders of Mariupol, having lasted so long, have made a significant contribution to the overall war effort - even if they eventually are overwhelmed", he tells the BBC.

"Russian resources are not unlimited and they lost a lot of equipment and people in a failed campaign to take Kyiv," Chalmers adds.

He says Putin’s maximum aim remains to replace the Ukrainian government with a regime to his liking - even the total absorption of Ukraine to Russia.

"The battle of Donbas is a case of sequencing - trying to achieve one thing at a time."

He says if Russia is successful in its Donbas assault, "which is possible but not likely", they would then move on to the south to attack Odesa and Kyiv.

"In retrospect, the Russian leadership will believe they made a strategic error trying to fight Ukraine on several fronts at the beginning of the war," Chalmers says.

The city of Izyum - known as the gateway to the Donbas region and the Black Sea - is experiencing fierce fighting as the Russians use it as a staging post to attack towns in the east.

Now, there are fears Izyum will become the next Bucha - where Russia is accused of war crimes against the civilian population, including executions and torture.

Izyum reportedly has the highest concentration of Russian troops in Ukraine.

The strategic city, located 70 miles south-east of Kharkiv, heads into the separatist-controlled east and fell completely to the Russians on 1 April.

While some civilian evacuations were carried out before Russian soldiers invaded, there are around 10,000 to 15,000 people still trapped according to officials.

Almost 80% of the city's residential buildings have been destroyed and train lines have been cut, the city's deputy mayor says.

People who have managed to flee Izyum told the BBC that it is on the edge of a humanitarian catastrophe.

For more than a month, civilians haven't had access to humanitarian help, with "no electricity, heating or water", head of the Izyum military administration, Stepan Maselsky, says.

Maselsky, who is in a Ukrainian-held area surrounding Izyum, says contact with civilians is being controlled by Russian forces, who won't allow people to enter or leave the area.

"We have unconfirmed reports of deportations [of civilians] to Russia - people are not allowed to move around inside the city," he says.

Image source, .

We've been focusing on Mariupol so far today - but let's take a look at the broader picture across Ukraine.

Russia's military has seized most of Ukraine's eastern border areas, and its forces have now fully withdrawn from around the capital Kyiv and northern Ukraine to Belarus and Russia.

Image source, .

Following the withdrawal, Russia refocused its efforts to launch a large-scale offensive in eastern Ukraine, intensifying fighting in the Donbas region.

Image source, .

Russia continues to build troops along its 300-mile eastern front, with satellite imagery showing a build-up of forces on Ukraine's border and convoys of vehicles travelling towards the front line.

Track the war in maps here.

Russia's Ministry of Defence claims its forces have hit 1,053 Ukrainian military facilities overnight.

In a Telegram update this morning, the defence ministry said it had destroyed 106 artillery firing positions and shot down six Ukrainian unmanned aerial vehicles.

It said its forces hit 73 military assets of Ukraine, among them:

• Four command posts
• 57 areas of Ukrainian manpower and military equipment
• Seven strong points and four ammunition depots
• Six tanks and nine armoured vehicles and
• One Msta-B howitzer battery weapon

It added that a high-precision missile strike killed up to 40 Ukrainian military personnel and destroyed seven military equipment units.

The Armed Forces of the Russian Federation said it continues "the special military operation in Ukraine".

The BBC has not been able to independently verify these claims.

Image source, .

As we've been reporting, Ukraine hopes to evacuate 6,000 people from the besieged city of Mariupol via humanitarian corridors on Wednesday.

However, the mayor, who has left Mariupol, says that there are still about 100,000 people left in the city.

Vadym Boichenko also warned that the agreement with Russia was only preliminary. If it holds, it will be the first on creating safe corridors since 5 March.

That agreement collapsed, and many people have been trapped in Mariupol for weeks without running water, power or other supplies.

It's a strategic target for Russia because it's a south-eastern port for Ukraine. Russia claims to control most of it, with the last Ukrainian defenders holed-up in the vast steelworks.

Image source, .