Image source, Getty Images

If you're just joining us, here are all the latest developments from Ukraine as the Russian invasion wraps up its 16th day.

• Ukrainian officials have accused Russia of bombing Belarusian settlements from Kyiv's airspace on Friday. In a message on Facebook, Ukraine's defence minister warned of the looming assault. The BBC has not been able to independently verify the claim.
• Speaking in a televised address, Ukraine's President Zelensky said his country had reached a turning point and was "on the way to victory".
• In the US, President Joe Biden announced fresh sanctions on Russia, including a ban on imports of Russian alcohol, seafood and diamonds. He also said the US would expand the list of Russian oligarchs subject to economic sanctions. These latest steps will be "another crushing blow to the Russian economy", Biden said.
• The UN's disarmament chief said the UN is not aware of any biological weapons programme in Ukraine, after Moscow alleged - without offering evidence - that there have been dangerous "biological activities" there. Ukraine denied the allegation.

• The US warned that Russia, not Ukraine, may be planning on using chemical or biological weapons against the Ukrainian people.

Jonathan Beale
Defence correspondent

Western officials say a third Russian senior military officer - at the rank of major general - has now been killed in Ukraine. They did not provide the name of the latest casualty, but said the major general was from the Eastern Military District.

Officials said that Russia would have around 20 major generals in Ukraine at present - three of whom have now been killed since the invasion began on 24 February.

In comparison three Russian major generals were killed during the entire conflict in Syria.

Western officials said it indicated that very senior officers had been trying to "lead from the front", either because of a lack of "situational awareness" or because their soldiers were fearful of moving forward.

Western officials believed that a US estimate that between 5,000 and 6,000 Russian troops had been killed in Ukraine was "in the right order".

Russia's forces continue to make limited advances with continuing problems with logistics and supplies - and were still meeting stiff Ukrainian resistance, the officials said.

Anti-tank and anti-aircraft weapons, including those supplied by the West, were being used to great effect, they said.

Russia's air force had also still failed "to gain control of the air", they added.

Image source, Getty Images

YouTube has announced that it is immediately blocking access to channels associated with Russian state media.

The video streaming giant referenced its policy blocking content that denies or trivialises well-documented events.

It said that Russia's invasion of Ukraine falls under that policy and that it will block access to channels including RT and Sputnik.

"Our Community Guidelines prohibit content denying, minimizing or trivializing well-documented violent events, and we remove content about Russia’s invasion in Ukraine that violates this policy," spokesman Farshad Shadloo said.

"In line with that, effective immediately, we are also blocking YouTube channels associated with Russian state-funded media, globally."

RT's main YouTube channel had more than 4.5 million subscribers prior to the ban, while Sputnik had around 320,000.

Andrew Harding
BBC News, Mykolaiv

There have been several air raid sirens in the port city of Mykolaiv today. The sound of artillery - muffled by heavy snowfall - has been audible throughout the day. Mostly Ukrainian fire, we believe.

Ukrainian forces in the city - on the Black Sea coast - have, for more than a week now, successfully thwarted a major Russian advance west towards the larger port of Odesa. If Mykolaiv falls, Russia is that much closer to control the entire southern coast, which would be symbolically and strategically important.

Mykolaiv’s governor Vitaliy Kim said Ukrainian soldiers had pushed Russian troops back some 15 or 20km (12 miles) towards the east and had even surrounded some Russian units.

“We are winning this fight, but not this war,” said Kim, in army fatigues, standing in an icy wind in the city.

The governor said a relatively weak Russian force had underestimated local resistance and expected to “be greeted with flowers”. But he warned that Russian reinforcements, and planes, could quickly turn the tide and enable the Kremlin to capture the whole Black Sea coastline.

Speaking to the UN on Friday, Ukrainian envoy Sergiy Kyslytsya condemned Russia, the "aggressor state", for its lies, war crimes and crimes against humanity.

“What will be the next target? One more residential building? One more maternity hospital?” he said. "Russian troops have already hit all of these sites."

Kyslytsya spoke about Mariupol, the southern coastal city, which is under near-constant assault from Russian forces.

"Russia's indiscriminate air strikes and shelling have almost destroyed Mariupol and killed 1,582 civilian residents of that city, according to the local administration," he said. "For the first time since World War Two people are being buried in mass graves in Ukrainian cities."

Read more about the humanitarian crisis in Mariupol.

Potential use of chemical weapons would present West with a tough decisionpublished at 18:29 Greenwich Mean Time 11 March 2022

18:29 GMT 11 March 2022

Nada Tawfik
BBC News

Right at the top of the Security Council meeting, the UN’s Under Secretary General of Disarmament Affairs, Izumi Nakamitsu, made clear that the UN was not aware of any biological weapons programmes in Ukraine.

Western nations slammed Russia for abusing its permanent seat on the council to spread its propaganda and to legitimise its violence against Ukraine.

The claims were called outrageous, utter nonsense and conspiracy theories. But more importantly, the US warned that Russia was creating another pretext for an attack.

The US ambassador to the UN, Linda Thomas-Greenfield, said the US had evidence that Russian forces could use chemical weapons in assassinations or tactical military operations. She said it was Russia, not Ukraine, that had a well-documented history of using deadly nerve agents, against opposition leader Alexei Navalny and former Russian agent Sergei Skripal.

The use of chemical or biological weapons in Ukraine - if it were to happen - would mark a dangerous escalation in this war and present Western leaders with a tough decision.

Right before the council meeting began, President Joe Biden said Moscow would pay a severe price if it used chemical weapons. The question is what more would the West do when it does not want a war with Russia, a conflict that Biden said would amount to a World War Three.

The UK's ambassador to the UN has condemned Russia's claims to have discovered evidence of biological weapons in Ukraine as "a grotesque lie".

Dame Barbara Woodward said Moscow is "sinking to new depths" with the claim and accused it of committing war crimes in Ukraine.

"We do not sit in this chamber to be an audience for Russia's domestic propaganda, and we should not allow Russia to use its permeant seat to spread disinformation and lies," Woodward said

"Russia has broken its commitments under the charter, but we must not let it subvert the multilateral system itself", she went on.

"As the UN said today, Russia is putting at threat the global framework for peace and security."

More from the UN security council meeting and China’s representative to the UN Zhang Jun has described multiple peace talks between Russia and Ukraine as “positive steps towards achieving peace”.

He says China will “play its part in de-escalating the situation”.

He also says China attaches “great importance to bio-safety and security” and “firmly opposes the development, possession and the use of biological and chemical weapons by any country”.

He says it would encourage any country that has not yet destroyed their stockpiles of chemical weapons to do so as soon as possible.

Zhang Jun says China has “noted with concern relevant information released by Russia” and believes it should be "properly addressed".

As we've reported, Russia has provided no evidence for its claims that Ukraine has developed biological weapons, and conducted "dangerous experiments" in co-ordination with the US. Ukraine denies the claim, which the US has called "laughable".

Image source, Getty Images

Russia's envoy to the UN has hit back at the organisation's findings that there is no evidence of biological weapons that have been developed in Ukraine.

Vasily Nebenzya has failed to produce any proof of his claims that Ukraine has created biological weapons, which the UN's disarmament chief Izumi Nakamitsu said she could find no evidence of.

He told delegates that "military development is a secret enterprise and those involved don't report to Ms Nakamitsu about it".

"Many of you said that you are unaware of military programmes in Ukraine, that doesn't mean that they didn't exist in actual fact," he added.

Image source, Getty Images

Ukraine's state Centre for Strategic Communications has warned that it cannot rule out the possibility that Belarus could join the Russian invasion in the coming hours.

The warning comes after a meeting between Russian President Vladimir Putin and Belarusian leader Alexander Lukashenko in Moscow, and Ukrainian officials warned that Belarusian troops could be ordered to cross the border on Friday night.

"According to preliminary data, Belarusian troops may be drawn into an invasion on March 11 at 21:00 (19:00 GMT)," the centre, which was established under the Ministry of Culture and Information Policy, said in a statement.

Officials alleged that Putin could order Russian bombers launched from Ukrainian territory to shell targets in Belarus, giving Lukashenko a pretext with which to launch an invasion.

The warning follows reports, which the BBC cannot independently verify, that Russian bombers launched an attack on a southern Belarusian village on Friday afternoon.

Ukraine's Defence Minister Oleksiy Reznikov said the attack was an attempt to "force the current leadership of Belarus into war against Ukraine".

Sarah Rainsford
BBC Eastern Europe Correspondent, Dnipro

The factory site that was bombed in Dnipro was in the middle of a residential area; there are blocks of flats all around now scarred by shrapnel and flying debris, their windows all blown out by the bomb blast.

At a nearby pre-school, we found a team of workmen boarding up windows.

A couple of blocks back, a woman told me it wasn’t the explosion that woke her first but the terrified screams of her 15-year-old son. They rushed to the stairs, but two more missiles hit nearby before they could make it to the nearby metro station and shelter.

Natalia broke down in tears as we talked, but like everyone I spoke to here today she was furious as well as horrified.

“We didn’t ask to be ‘saved’ by Russia. We had everything we needed. We speak Russian too!” Natalia told me, through floods of frightened tears. “I think it’s a miracle we survived. We are alive... that’s the main thing."

These people are Russian speakers, they were never hostile to Moscow. And yet it’s Russia, under Vladimir Putin, that’s now targeting and killing them.

Frank Gardner
BBC Security Correspondent

Image source, AFP

Chemical weapons are any kind of munitions that carry toxins or chemical substances that attack the body’s system.

There are different categories of chemical weapons:

• Choking agents like phosgene attack the lungs and respiratory system
• There are blister agents like mustard gas that burns the skin and blinds people
• And there are nerve agents, which interfere with the brain’s messages to the body’s muscles. A tiny drop of these can be fatal

All of these so-called chemical agents can be used in warfare in artillery shells, bombs and missiles. But all are strictly prohibited by the Chemical Weapons Convention.

They’ve been used in war in the past – in World War One, in the Iran-Iraq war in the 1980s and more recently by the Syrian government against rebel forces. Novichok was used by Russia to poison Sergei Skripal and his daughter in Salisbury in 2018. Russia denied it.

The relevance here today is that Russia is accusing Ukraine of developing weapons in secret laboratories. Ukraine says this is ludicrous and it doesn’t have either chemical or biological weapons. Both Russia and Ukraine have signed the Chemical Weapons Convention.

The Pentagon worries that by Russia accusing Ukraine of having chemical weapons and planning an attack, it could be creating a so-called "false flag" situation that Russia would use as an excuse to carry out its own chemical weapons attack.

The fact is that if you have a protracted war where the attacking forces are trying to break the will of defending forces then chemical weapons are, unfortunately, one very effective way to achieve that. It’s what Syria did in Aleppo.

US ambassador to the United Nations, Linda Thomas-Greenfield, goes on to tell the UN Security Council that Russia has a well documented history of using chemical weapons.

Thomas-Greenfield says the US “has serious concerns that Russia may be planning to use chemical or biological agents against the Ukrainian people”.

She also says she believes Russia could use chemical or biological agents “for assassinations as part of a staged or false flag incident, or to support tactical military operations".

US ambassador to the United Nations Linda Thomas-Greenfield tells the UN Security Council: “Ukraine does not have a biological weapons programme.

"There are no Ukrainian biological weapons laboratories supported by the United States. Not near Russia’s border or anywhere”.

Thomas-Greenfield says Ukraine operates its own public health laboratories to detect and diagnose diseases like Covid-19, adding the US has assisted Ukraine “to do this safely and securely”.

She says the work has been done "out in the open”, adding: "It is Russian that has long maintained a biological weapon programme in violation of international law".

More now from the UN Security Council, where Russia's ambassador Vasily Nebenzya has been claiming that Moscow's forces have discovered evidence of attempts to cover up biological weapons research by Ukraine.

Nebenzya claimed that Ukraine had used the coronavirus pandemic as a cover with which to advance its research, and told delegates that the country had sought to spread biological weapons by infecting migratory birds and bats.

He also accused the US of attempting to create biological weapons that can target specific ethnic groups.

Nebenzya did not provide any evidence for his claims, and the US ambassador, Linda Thomas-Greenfield, says the claims are an attempt to "manufacture a pretext for attack".

"Russia is attempting to use the security council to legitimise disinformation and deceive people to justify President Putin's war of choice against the Ukrainian people," she said.

Frank Gardner
BBC Security Correspondent

Image source, EPA

Biological weapons are different to chemical weapons. It’s a phrase used to describe the weaponisation of a dangerous pathogen such as Ebola.

Russia has accused Ukraine of working with the US on biological weapons. One of the reasons is Ukraine, like many countries in the world, has been working on research on Covid and other pathogens and looking at ways to defend populations against them.

Ukraine has denied any allegations it is working on biological weapons.

The problem is there is a potentially a grey area between working on ways to protect your population from harmful pathogens, and secretly working on how they could be used as a weapon. Russia did not produce any immediate evidence of Ukrainian misdoings in this area.

Russia, when it was part of the Soviet Union, controlled a truly massive biological weapons programme, run by an agency called Biopreparat. After the end of the Cold War, scientists went in to dismantle it in the 1990s. They found that the Soviets had mass produced and weaponised anthrax, small pox and other diseases after testing them on live monkeys in southern Russia. They even loaded anthrax spores into the warheads of long-range inter-continental missiles aimed at Western cities.

Russia's ambassador to the UN has claimed that Moscow's forces have found evidence of an attempt to clear up evidence of biological weapons in Ukraine.

Speaking at a meeting of the UN Security Council convened at Russia's request, Vasily Nebenzya claimed that Russian forces had found evidence of a network of "at least 30" biological research labs aimed at strengthening several "lethal diseases".

He said that "very dangerous biological experiments" had been conducted at the sites in co-ordination with the US.

Nebenzya did not provide any evidence for his claims and the UN's disarmament chief Izumi Nakamitsu has said it is not aware of any biological weapons programme in Ukraine.

Meanwhile, the US has called such claims from Russia "laughable", and warns that Russia could use them to justify its own potential use of similar weapons against Ukraine.

The UN's disarmament chief Izumi Nakamitsu says the United Nations is not aware of any biological weapons programme in Ukraine.

The UN's Security Council was convened following Russia's request to discuss Moscow's claims, presented without evidence, of US "biological activities" in Ukraine.

Nakamitsu also addressed the “worrying issue” of the safety and security of nuclear power plants in Ukraine

She said an accident involving nuclear facilities in Ukraine “could have severe consequences for public health and the environment”.

Nakamitsu says “all steps must be taken to avoid it”.

She says the possibility of an accident caused by failure to a reactor’s power supply, or the inability to provide regular maintenance “is growing by the day”.

Image source, Getty Images

More now from US President Joe Biden, who has been announcing further sanctions on Russia to punish it over its invasion of Ukraine.

He has just announced a ban on imports of Russian alcohol, seafood and diamonds, moves which are designed to put pressure on Moscow's economy by targeting some of its most valuable exports.

"We're banning goods from several signature sectors of the Russian economy," Biden said.

He also announced that the US will add the names of several more Russian oligarchs to the list of sanctioned individuals.

Biden warned that Russian President Vladimir Putin "cannot pursue a war that threatens the very foundations of international peace and stability, and then ask for financial help from the international community".

Image source, Getty Images

Ukraine's former president says it would be a "catastrophe" for the world if President Putin is successful in his invasion of Ukraine and clings onto power in Russia.

Viktor Yushchenko, who served as Ukraine's leader from 2005 to 2010, has been telling the BBC's PM programme that he can only foresee two possible ways in which the current conflict ends.

"Either we push the last Russian soldier from Ukraine, and it will be a partial response to victory in this war," he says.

"There is another option, which is a theoretical one, which is when the last Ukrainian hero dies," he adds.

"There is also Russia, which is an enslaved nation if it continues under Putin, and that would be a catastrophe for the whole world."