The suspected poisoning of Russian billionaire Roman Abramovich at peace talks earlier this month has nothing to do with reality, the Kremlin says, according to Reuters news agency.

They say the story is part of an "information war".

The Kremlin also says Abramovich is not an official member of the Russian delegation in Turkey - although he has been pictured at the talks with Ukraine.

Earlier we told you about an attack on the regional administration office in the southern Ukrainian city of Mykolaiv.

The city's governor, Vitaliy Kim, has now posted a photo showing a gaping hole in a tower block.

The authorities say 17 people have been freed from the rubble, but others are still missing - most of them civilians.

Governor Kim said they were searching the wreckage.

"The regional administration building was hit, half the building was destroyed," he said.

"Concerning people and casualties, we are all in God's hands and the majority escaped miraculously, I don't know how. Now there are eight civilians whom we are hoping to pull out from the rubble."

Earlier today, US think tank Institute for the Study of War published its latest assessment of the fighting in Ukraine.

It found that Russian forces have not abandoned their objective to capture Kyiv, despite Kremlin claims that they will concentrate on eastern Ukraine.

Their latest report also says:

• Ukrainian armed forces recaptured Irpin, northwest of Kyiv, and Ukrainian counterattacks around the capital will likely thwart Russian operations from encircling it
• Russian forces have been stalled in northeastern Ukraine and did not conduct offensive operations on the cities of Chernihiv, Sumy or Kharkiv in the past 24 hours
• Russian conscription efforts might be unable to provide Russian troops ready for combat operations for some time. Russia's pool of trained replacements remains low and new recruits will require "months" to get operation-ready
• The Russian military has likely already deployed most of its reserves to Ukraine. Unspecified units continue to be deployed but officials observed a “significant decrease in the intensity of traffic from the depths of the Russian Federation”
• Ukrainian forces say that Russian forces are regrouping to resume major operations to capture the entirety of the Donetsk and Luhansk regions

Image source, Institute for the Study of War

Russian news agency RIA has shared a picture of Roman Abramovich looking well at talks in Istanbul on its Telegram channel, external.

The Chelsea FC owner's spokesman says he suspected he had been poisoned during a previous round of talks.

He is said to have suffered sore eyes and peeling skin. A source close to Abramovich told the BBC he had now recovered and was focused on negotiations to try and end the war.

The exact nature of his position in the talks is unclear, but a spokesperson for the oligarch previously said his influence was "limited".

Image source, RIA

Before today's talks in Istanbul started, Ukraine's foreign minister Dmytro Kuleba advised anyone going to the negotiations with the Russian Federation "not to eat or drink anything, and preferably avoid touching any surface".

He was speaking during an interview with Ukrainian news channel Ukrayina 24.

The warning came after the suspected poisoning of Russian billionaire Roman Abramovich and Ukrainian negotiators earlier this month at peace talks on the Ukraine-Belarus border.

There is some scepticism about the alleged poisoning and an unnamed US official was quoted by Reuters as saying that intelligence suggested the men's symptoms were due to "environmental" factors, not poisoning.

As we've been reporting, Abramovich has been spotted at the negotiations, in pictures broadcast by Turkish media.

A missile strike has hit an administrative building in the southern city of Mykolaiv, its governor says.

According to AFP, Vitaly Kim said most people inside the building "escaped miraculously" but several civilians and soldiers were unaccounted for.

Mykolaiv, a port city, has been under assault for weeks.

Image source, .

There's been much speculation about Russia wants from the peace talks, just beginning in Istanbul.

According to the Financial Times, external, Russia has dropped demands that Ukraine is "denazified" and is prepared to let it join the European Union as long as it is not militarily aligned.

The paper quotes four people close to the talks saying a possible deal would involve Ukraine abandoning its drive for Nato membership in exchange for security guarantees.

But it does not contain discussion of three initial core Russian demands over denazification, demilitarisation or legal protection fort the Russian language, the FT says.

Ukraine's Foreign Minister Dmytro Kuleba has said his county was not "trading people, land or sovereignty", while Kremlin spokesman Dmitry Peskov has said talks have so far not yielded substantial progress.

Tom Bateman
BBC Middle East correspondent in Istanbul

Image source, TRT

Russian billionaire Roman Abramovich - the owner of Chelsea football club - has been spotted inside the Istanbul talks.

In pictures broadcast by Turkish media, he is seen sitting at a table alongside Ibrahim Kalin - a spokesman for President Erdogan, and is wearing translation headphones.

He’s not at the main table of the Russian and Ukrainian delegations.

Kalin has reportedly helped coordinate meetings between the Russian oligarch and a member of the Ukrainian delegation in Istanbul hotels.

The presence of Abramovich suggests he’s still involved at some level in the mediation attempts.

Yesterday reports emerged that he suffered symptoms of suspected poisoning at peace talks on the Ukraine-Belarus border earlier this month.

Ukraine hopes to be able to evacuate civilians from some towns and cities besieged by fighting today, deputy prime minister Iryna Vereshchuk says.

This would include trying to establish a route out of the encircled port city of Mariupol - where 160,000 people remain trapped - for private vehicles, according to Reuters.

Yesterday, Ukraine warned some of the routes were unsafe because of potential attacks by Russian forces.

Tom Bateman
BBC Middle East correspondent in Istanbul

Image source, Reuters

The Russian and Ukrainians delegations have now arrived at the Dolmabahce - President Erdogan’s office on the banks of the Bosphorus here in Istanbul.

They're sat along a long table facing each other. The Turkish leader has addressed them, followed by applause.

These are the first face-to-face talks in over a fortnight but hopes of any breakthrough are low.

Erdogan spoke of his “deep sorrow” that conflict has entered its fifth week, saying Turkey’s friendship with both countries gave it an obligation to mediate.

"It is in the hands of both sides to stop this tragedy," he said.

Turkey is a Nato member but retains strong ties with Russia. Mr Erdogan has resisted joining the West’s sanctions against Moscow - one of the few countries still to do so.

Continuing with his welcome, Recep Tayyip Erdogan says there is a lot resting on the talks.

He says a "fair peace" will not have a loser and that the conflict continuing benefits no one.

"At such a critical time we are pleased to welcome you and to contribute to your efforts to establish peace," he says, adding: "I wish that our meetings and discussions will prove to be auspicious for your countries, our region and all humankind."

He has called for an immediate ceasefire and says stopping the tragedy is up to both sides.

Image source, Reuters

Turkey's President Recep Tayyip Erdogan says both Ukraine's Zelensky and Russia's Putin are "valuable friends", as he sets the scene for talks in Istanbul this morning.

He says progress at the talks would pave the way for the leaders to meet - and that Turkey could host that too.

He also tells the Russian and Ukrainian teams that both sides have "legitimate concerns" but that we have reached a moment when talks need to yield "concrete results".

If you're just joining us this morning, welcome. Here are the latest developments:

• Russian and Ukrainian delegations have arrived in Istanbul for the first talks in weeks. Ukraine says its priority is to negotiate a ceasefire, but both the US and Ukraine have also expressed scepticism about Russia's intentions
• Ukrainian President Volodymyr Zelensky pleaded overnight for world powers to toughen sanctions on Russia, including an oil embargo

• Sources close to the Russian billionaire Roman Abramovich say he suffered symptoms of suspected poisoning at peace talks earlier this month, along with two Ukrainian peace negotiators were also said to have been affected. He has now recovered.
• US President Joe Biden has said he won’t “walk back” his controversial comment that Vladimir Putin “cannot remain in power”. Biden said he was expressing the "moral outrage" he felt, rather than "articulating a policy change"
• The UK's Ministry of Defence believes that Russia is maintaining blocking positions, while it resets its forces
• A senior US defence official confirmed that Ukraine has managed to retake the town of Trostyanets near the northen region of Sumy and that Russia's advance on Kyiv has stalled amid a shift in focus towards the eastern Donbas region

And with that, this is Tessa Wong and Zubaidah Abdul Jalil in Singapore, and Andrew Clarance in Delhi signing off. We are handing over to our colleagues Emma Owen and Doug Faulkner in London, who will continue updating you on the latest developments.

Image source, Getty Images

Another assessment of the fighting - this time from Jack Watling, research fellow for land warfare at think tank the Royal United Services Institute.

He says Irpin, to the north of Kyiv, is under Ukrainian control once more and shows the disparity in morale, equipment and resupply between the two sides.

Normally taking a terrain point requires three times the number of opposing troops and even more in an urban environment, he says.

"It shows that where the Russians don't have their artillery restocked they are really vulnerable at the moment," he says.

Mr Watling also says that it is very likely Mariupol will fall "imminently".

Russian forces will then "start to wrap around" the Ukrainian units in the Donbas region to the east, he says, which includes some of Ukraine's best units which have been fighting the longest.

"They will be low on ammunition, they will be very tired and that would be a major setback for the Ukrainian military," he says.

The UK's Ministry of Defence has , externalreleased its daily assessment of the fighting in Ukraine.

It says Ukrainian forces have conducted "localised" counter attacks north west of Kyiv with some success, with the Russians pushed back from a number of positions.

But the MoD warns that Russian forces still pose a significant threat to the capital through its strike capability.

In the south, the MoD says Russia has maintained its offensive on Mariupol with heavy shelling but says Ukrainian forces still control the city centre.

Elsewhere, Russian troops are "maintaining blocking positions while attempting to reorganise and reset their forces", it says.

British Foreign Secretary Liz Truss has accused Russia's President Vladimir Putin of using the "abhorrent tactic" of abducting Ukrainian civilians.

In a tweet, Truss said that Putin was "resorting to desperate measures".

Her comments came after a Ukrainian human rights group, Zmina, said it had identified dozens of people who had been taken captive.

The group also claims that "thousands" of Ukrainians have been taken to Russia against their will.

It has been challenging to ascertain the exact number of casualties among Russian troops so far, with both the Ukrainian and Russian governments providing wildly varying estimates.

But a recent in-depth investigation by BBC Russian has shed more light about the reported deaths of troops, as BBC World Service correspondent Olga Ivshina points out in a Twitter thread.

She points out that the majority of confirmed losses are paratroopers - which can be explained by the fact that paratroopers are often used by Russia as the main storming force.

The deaths of more than 10 Russian specialists like military pilots, flight mechanics and sniper-pilots has likely come at great cost to Russia, with the training of one fighter pilot estimated to cost $3m over a period of seven to eight years.

Our correspondent also points out that it appears the regions of Dagestan and South Ossetia regions are facing the heaviest losses of their servicemen - though this data is based on information published by each region, as shown in the map below.

There is also evidence of growing pressure on local journalists who have reported on military losses. Some earlier reports have been deleted - sometimes in a day or two, while others within the hour.

One Siberian journalist told the BBC all local media outlets were instructed by the regional government not to publish any data on losses in Ukraine.

"They say, now there is no need to make a fuss, we will find a way to commemorate your boys later," the journalist said.

Russian armed forces on Monday carried out a missile strike on the town of Lyubotyn in the northeast Kharkiv region, flattening several houses, say Ukranian officials.

The Kharkiv regional prosecutor's office says in a Telegram statement that the strike injured seven people. Officials recovered the body of one person from the rubble.

Image source, Kharkiv regional administration

Image source, Kharkiv regional administration

After US and China, India is the third largest consumer of oil, over 80% of which is imported. In 2021, the country bought about 12 million barrels of oil from Russia, which is just about 2% of its imports.

Russia is seeking to sell its discounted oil to new markets as Western sanctions choke the country's economy - and India is taking advantage of these discounts.

In January and February, India did not import any oil from Russia. But since then, orders for six million barrels have already been placed, says Kpler, a commodities research group.

The Indian government says it is "still a drop, literally a drop, in a larger bucket" of its oil imports globally.

After Russia invaded Ukraine, there were fewer buyers for Russia's Ural crude oil, and its price has fallen.

Analysts at Kpler say that while the exact price is not known, the Urals discount to Brent crude - which is the global benchmark for crude - widened to $30 per barrel.

This depreciation in the price of Ural "means that India and China are likely to purchase at least some of this [Russian] crude at a significant discount," says Matt Smith, an analyst at Kpler.

Read more on the impact of financial sanctions on Russia oil.

In its latest update, Ukraine's General Staff of the Armed Forces says Russian forces are continuing to launch missile strikes on residential neighbourhoods across the country, focusing on targeting fuel storage compartments in an effort to "complicate logistics" and "create conditions for a humanitarian crisis".

In recent days fuel depots in several cities such as the capital Kyiv, as well as Lviv, Rivne, Zhytomyr and Lutsk, have been reportedly hit.

The Ukrainian military also claims that Russian units are terrorising local populations in the capital Kyiv, Zaphorizhzhia in the south-east, Kherson in the south and Kharkiv in the east by looting, kidnapping and holding civilians hostage.

The BBC cannot immediately verify some of these claims. But as we've reported earlier this week, some Ukrainian civilians are being arbitrarily detained and subjected to enforced disappearances in Russian-controlled areas.