US spymaster Gen James Clapper who oversaw the CIA, FBI, NSA and served as one of President Barack Obama's principal advisers has offered some insights into what intelligence work might be going on to establish what Russian President Vladimir Putin's state of mind is.

"Putin has been largely isolated, particularly so in the last two years with the pandemic, and compounding that is the fact that he has very few people that really have access to him - that makes gathering intelligence you have faith and trust in very difficult, so a lot is read into what he does and says publicly," he told BBC Radio 4's Today programme.

Intelligence officers will be poring over images and speeches both in content and manner of delivery, he says.

Putin has done a lot of things that don't conform "with his traditional buttoned down, cold, pragmatic, machine-like demeanour", he says.

Asked whether he is rational, "one hopes that if you're dealing with a head of state who has his finger on the button for the largest nuclear arsenal on the globe, that he is thinking rationally. I think from many perspectives, he is very rational... But I do know his behaviour and his demeanour have changed recently over what it was."

Are we paying the price for mistakes made in the past, not acting when lines have been crossed like when Crimea was annexed or when chemical weapons were used in Syria?

The now US President Biden was vice-president at the time of those developments, and will have lived through all this, which would have led to him tempering his public statements and being very measured, Clapper says.

Image source, Getty Images

More now on the situation in the north-eastern Ukrainian city of Kharkiv, which has been under Russian attack.

Almost a thousand buildings have been destroyed there as a result of Russian shelling, Ukraine's state emergency service has said.

Most of these are residential buildings, the SES said.

Russian forces have been relentlessly shelling Kharkiv, which lies just 30 miles (50km) from the border with Russia, for more than three weeks.

At least 500 civilians have been killed there, Ukrainian officials say.

Ishaq Khalid
BBC News, Abuja

One of the Nigerian students who fled the war in Ukraine has died in his hometown of Sokoto in northern Nigeria.

It’s not yet clear what exactly caused the death of Huzaifa Habibu.

His father, Habibu Halilu Modaci, told the BBC that he was taken to hospital after complaining of discomfort and loss of appetite.

The 22-year-old student, who was studying medicine in Ukraine, was due to graduate next year and had arrived back in Nigeria barely two weeks ago.

It was his first time returning home in three years.

Mr Modaci said that his son had narrated the horrors of the war and the scramble to flee Ukraine.

Nigeria has evacuated more than 1,500 of its students from Ukraine following the Russian invasion last month.

But there are around 100 more still trapped in the city of Kherson.

Image source, Getty Images

More than 2,000 children are born through surrogacy every year in Ukraine, the majority to foreign couples.

The country has around 50 reproductive clinics and many agencies and middle-men who match couples - known as "intended parents" - to surrogates.

But the war has thrown the lives of these surrogate mothers, their babies, and their intended parents - into uncertainty and chaos.

Nastya - a surrogate pregnant with twins - was only weeks from her due date when the war broke out. She went into labour a few days later.

"We spent the entire time in the hospital in a bomb shelter," she told the BBC.

Kharkiv was under heavy bombardment and the hospital's basement was packed from wall to wall with mattresses and baby cribs.

Nastya camped out in a storage room with her two other children, sleeping on sofa cushions on the floor, underneath shelves piled high with files and paperwork.

She delivered two healthy baby boys, but their parents couldn't travel to Ukraine to collect them.

Instead, Nastya, her two sons, and the newborn twins had to travel across Ukraine to reach the border, risking their safety, before she could deliver them to their parents.

Read more about Nastya and the impossible choices of surrogate mothers here.

BBC Radio 5 Live

Image source, Getty Images

Victoria, 27, who managed to escape from the besieged southern Ukrainian city of Mariupol, tells 5 Live Breakfast how she left family behind as she fled to a village about 20km (12.5 miles) away.

"My city is absolutely destroyed," she says, her voice trembling as she describes hearing the daily shelling of Russian attacks.

"People stay in the basement, but that isn't safe. They are bombing so hard basements are being destroyed."

She says many people don't have access to food and water.

"Three children I know died of dehydration. It is the 21st Century and children are dying from dehydration in my city. They are starving now."

Victoria adds that she was unable to help other family members leave Mariupol and is desperate to "take them out".

"I will stay in Ukraine and try and save my family in Mariupol. Mariupol is my life, I don't understand why I should leave my city, my country because of Russia."

Looking ahead now to which fronts may next become critical in the war, Dr Sidharth Kaushal, sea power research fellow at defence think tank Royal United Services Institute, says a possible attack from the water on the strategic port city of Odesa is unlikely because of the limited capabilities Russia has in the region.

He says such an assault would only really work in tandem with a ground advance - but as ground forces have not progressed past Mykolaiv in the west, he says he would expect an amphibious assault to be "relatively unlikely in the near term".

He adds Russia could be using their sea force as a kind of "feint", which forces the Ukrainians to commit forces to the defence of Odesa and prevent them from using these forces elsewhere like in Mykolaiv.

On the question of whether Russia might use chemical weapons in Ukraine, he says they still have conventional weapons "with which to inflict pretty substantial amounts of pain on the Ukrainian society".

He feels the use of chemical weapons is unnecessary for the Russians right now, though it can't be ruled out in future.

Image source, Getty Images

Ukrainian military are reporting that a company that produces and repairs Russian tanks has suspended work at its plant in the central Russian region of Chelyabinsk due to a shortage of imported parts.

In a statement posted to Facebook, the General Staff of the Armed Forces of Ukraine reports that manufacturer Uralvagonzavod has had to pause production at the facility "due to the lack of receipts of foreign-made components".

Ukrainian military information and consultancy company Defense Express reports that Uralvagonzavod provides the only plant that carries out the assembly of tanks.

It goes on to report that the manufacturer routinely uses Western components.

There are no reports referring to the Uralvagonzavod facility in Russian media and the BBC has not been able to confirm the information in the Ukrainian statement.

Russian forces appeared to be 'stalled in place', due to achieving limited gains, the UK's ministry of defence said in its latest update that.

But in a Twitter post, it added Ukrainian forces continued to "repulse" Russian attempts to take over the southern port city of Mariupol - one of the most fiercely contested cities in the war so far.

Image source, Reuters

If you're just joining us, here are some of the key developments on day 27 of Russia's invasion of Ukraine:

• US President Joe Biden has given his strongest warning yet that Russia may be preparing to use chemical and biological weapons in Ukraine
• Biden says Russian leader Vladimir Putin has "his back to the wall" as a result of Ukrainian resistance, and there was a danger he could resort to more severe tactics
• The UK's Ministry of Defence says Russian forces appear to be "stalled in place", with Ukraine "continuing to repulse" attempts to occupy the besieged southern city of Mariupol
• Ukraine says a further 8,000 people were evacuated from conflict zones on Monday. Deputy Prime Minister Iryna Vereshchuk said this included around 3,000 people from Mariupol

• Ukrainian leader Volodymyr Zelensky has again called for direct talks with Putin, saying it would not be possible to negotiate an end to the war unless they met

• And Ukraine's military says Russian forces have "increased their aviation presence in Ukraine's airspace" in the past 24 hours

Image source, PA Media

Russian hoaxers have published footage online from a call they made to UK defence secretary Ben Wallace.

In the recording, Mr Wallace can be heard speaking to a man, who he revealed last week, was an "imposter" posing as the Ukranian PM.

Vladimir "Vovan" Kuznetsov and Alexei "Lexus" Stolyarov posted the video online. The duo have targeted a number of public figures and politicians in the past, including then-foreign secretary Boris Johnson in 2018.

The UK government has blamed Russia for targeting its ministers with fake calls about the conflict in Ukraine.

Read more here

Rescue teams in Ukraine are racing to put out fires and clear the rubble from destroyed buildings across major cities, Ukraine's State Emergency Services (SES) said on Tuesday.

Search works and clearance operations were carried out in the capital city Kyiv and Shevchenkivskyi districts of Kharkiv in eastern Ukraine.

SES units have also been extinguishing fires in apartment buildings, private facilities, and other buildings caused by shelling, in cities such as Kyiv, Slobidsky in the northeast and industrial districts of Kharkiv.

Pyrotechnic units also continued disposing of undetonated explosive devices, the SES said.

"Today I'm going to cross the Ukrainian border and fight against our common old enemy - Moscow troops."Pavel Kulazhanka is one of many Belarusian dissidents who has left life behind to fight alongside Ukrainian forces against Russia.

He says it is also "a fight for their motherland - Belarus."

"Without a free and independent Ukraine, there is no independent and free Belarus."

This footage - verified by the BBC - shows thermobaric rockets, also known as vacuum bombs, being launched in Ukraine.

The video, from the People's Militia of the self-declared Donetsk People's Republic, shows the rockets being fired from a Russian-made TOS-1A multiple rocket launcher.

Thermobaric weapons are controversial because they are much more devastating than conventional explosives of similar size, and have a terrible impact on anyone caught in their blast radius.

Read more: What is a thermobaric or vacuum bomb?

Image source, Getty Images

US President Joe Biden said that only India among fellow Quad allies - the United States, Japan and Australia - has shown itself to be "somewhat shaky" in its response to Russia over the invasion of Ukraine.

US, Japan and Australia have sanctioned Russian entities, but India has not imposed sanctions and has also abstained from three votes condemning Moscow at the UN.

India has said the escalation of tensions "is a matter of deep concern" and has reiterated that the issue can only be resolved through diplomatic dialogue.

Biden lauded other allies saying "we have presented a united front throughout the Nato and in the Pacific" in response to Russian President Vladimir Putin.

"The Quad - with the possible exception of India being somewhat shaky on some of these - but Japan has been extremely strong, so is Australia in terms of dealing with Putin's aggression."India has had to walk a diplomatic tightrope over Ukraine as it tries to balance ties with Moscow and the West. Russia continues to be India's largest arms supplier.

India is also considering buying Russian oil at a subsided rate with reports that a state-owned company has signed a deal to import 3 million barrels of crude, external from a Russian company,

Josh Parry
LGBT+ Reporter, BBC News

Hundreds of transgender women have been turned away at the Ukrainian border while attempting to flee the country, due to their passports still carrying their birth name and gender, charities say.

Changing the gender and name listed on their passport requires a lengthy process, involving several psychiatric assessments - meaning many of the country's transgender population don't go through with it.

But current rules ban Ukrainian men aged 18 to 60 from leaving the country - meaning anyone whose passport says "male" is likely to be turned back at the border.

One of Ukraine's main transgender charities estimates there are hundreds of trans women attempting to flee, but that 90% of those it is in touch with have so far failed.

In its daily update, Ukraine's ministry of defence said that Russian forces have stockpiles of ammunition and food that will last "no more than three days".

Here is what else their statement says:

• Russian forces have three days worth of fuel supplies, which are replenished by tank trucks. They have been unable to meet the needs of gathering troops.
• Over the past 24 hours, the Ukrainian Air Force has struck nine Russian air targets - one aircraft, six unmanned aerial vehicles (UAV) and two helicopters.
• In Okhtyrka, a small city in Sumy Oblast in central Ukraine, 300 Russian servicemen refused to carry out hostilities on Ukraine, and have left the area of the operation.
• Ukrainian forces defended 13 attacks and destroyed 14 tanks, eight infantry fighting vehicles, two multi-purpose towing vehicles, three artillery systems and four other vehicles.

The BBC could not independently verify these claims.

It's 07:30 in Kyiv. If you're just joining us, or catching up, here's a round-up of the latest developments:

• Biden warning: The US president says there are clear signs Vladimir Putin may be preparing to use chemical and biological weapons in Ukraine. Biden says the Russian leader "had his back to the wall" as a result of Ukrainian resistance, and there was a danger he could resort to more severe tactics
• Zelensky defiant: Ukraine's president says his country will never bow to ultimatums from Russia - after Moscow said it would allow people out of Mariupol if Ukraine surrendered the besieged city. He's also called again for direct talks with President Putin "in any format" to end the conflict
• Russia steps up air assault: The Ukrainian military says Russia has boosted its aerial presence in Ukraine's air space in the past 24 hours
• Russian casualties claim: A Russian news outlet that briefly published what it said were the official numbers for the number of servicemen killed in Ukraine - nearly 10,000 dead and over 16,000 wounded - has said it was the victim of a hack
• UK hoax video: A video clip from a Russian hoax call made to the UK Defence Secretary Ben Wallace has been published online

Image source, Getty Images

Russian Olympic swimming champion Evgeny Rylov has lost his sponsorship deal with Speedo after he attended a rally hosted by Vladimir Putin in Moscow last week, news website insidethegames reports, external.

Rylov, who won two gold medals at last year's Tokyo Olympics, was seen at the rally sporting a letter "Z" on his outfit - the symbol which has come to identify Russia's invasion of Ukraine.

The sport's world governing body Fina said it was "deeply disappointed" by Rylov's appearance at the rally and would investigate.

Swimwear maker Speedo told insidethegames it had "terminated the sponsorship of Rylov with immediate effect" following his attendance at the event.

Russian forces have "increased their aviation presence in Ukraine's airspace" in the past 24 hours, Ukraine's military says.

"In addition to the use of many unmanned aerial vehicles, the enemy uses bombers, assault and fighter aircraft, cruise missiles, and ballistic missiles in various directions," Ukraine's Air Force Command said in a statement.

It added that on Monday Ukraine destroyed a Russian aircraft, two helicopters and six drones. The BBC has not verified these claims.

The economic effects of the conflict are being felt across the world.

Jia Ruiying, the owner of Singapore's only Russian supermarket, has been telling the BBC how it has affected her business.

Her customers are panicking about not being able to find the goods they need for their families, she says. "Many of them tell me they feel helpless."

Her supply lines have been badly affected, and products from Ukraine are fast running out of stock.