welcome to bbc news. our top stories: ukraine's president accuses moscow of nuclear terror amid reports of the biggest power station being shelled. civilians are also under fire. this isjust a0 miles from the capital, kyiv. president putin remains undaunted. translation: | will never| renounce my conviction that russians and ukrainians are one people. the southern city mariupol has become a city under siege as power and water supplies are cut off by relentless russian shelling. washington, though, is turning up the pressure on putin, imposing fresh sanctions on oligarchs and associates of the russian media.

welcome. president volodymyr zelensky has accused russia of nuclear terror after russian forces invited the large nuclear power station, causing a fire. authorities say the plant which is the biggest of its plant in europe is secured, radiation levels are normal. president zelensky had a phone call with president biden and briefed him with the situation at the plant. the foreign minister said russians must immediately stop firing if a major disaster is to be prevented. our correspondence oui’ correspondence gave me our correspondence gave me this update. as you said, never good when the nuclear power

plant in europe catches fire, when smoke is seen around what now seems to be the perimeter, this administrative building, so not the actual reactors themselves, which is a relief to people, but the us president has been speaking to the ukrainian president about it. we are hearing updates about this plant from the us energy secretary. they are saying it has robust containment structures and the reactors have been safely shut down. so, from that point of view, less concerning, but both president zelensky and biden are appealing to the russians to let firefighters in and appealing for this area to stop, so russian tanks were trying to take hold of the plant in the last couple of days, but there was resistance from workers and residents of the area. this seems to have escalated in shelling, which is blamed on the russians by a neighbouring mayor, that caused the smoke to rise. just bringing our viewers into this conversation. just to say we are looking at pictures of that nuclear plant. it is reasonably difficult to work

out exactly what has been going on there. we have been scanning these as for the last couple of hours. bring us up to date with the iaea. the iaea has tweeted the director—general has spoken with ukraine's prime minister, the international energy agency, and the ukrainian operator said you have to watch out for this serious situation and have appealed for halt of use of force. the president indicating in a video message he has just released on facebook that this might be deliberate. he is saying it is. he says russian tanks have fired on the nuclear units, they are equipped with thermal images so they know where they are shooting, and then release this huge warning for europe. he says ukraine has 15 nuclear units. if there is an explosion, that is the end of europe, the evacuation of europe. the only immediate european action can stop russian troops. you can see how this incident on the battleground of war in ukraine really can be so incendiary. and also how difficult

it is to get accurate information. an hour or so ago, we were here and there was one piece of information we were reading out that said the site is secure. the latest information i have coming up according to the afp newsagency — russian troops preventing firefighters from accessing the blaze at the nuclear plant according to ukrainian rescuers. so this situation does change reasonably quickly. that's right. the accusations have taken a political dynamic. you have got the president of ukraine accusing them of a deliberate attack, firefighters not allowed in. you can shut down the reactors, is what we hear from the americans, but what about the fire itself that is potentially ongoing? we are now seeing on the news services we are getting into the building that firefighters have been given access to that nuclear plant. we will continue to update you with the story. joseph is a nuclear policy institute. he gave me his assessment of the situation.

like so much else in the last week, we are using the word unprecedented. this has never happened before. a nuclear power plant has never come under attack like this. the closest we came was worries after the 9/11 attack in the united states, that terrorists might target a nuclear power plant or the spent fuel pools around the nuclear power plant to release a kind of chernobyl or fukushima type disaster. but this is tank fire. this is not a terrorist trying to get in. this is armoured vehicles shelling a nuclear power plant. i cannot overstate how serious the situation is. it's good that we're getting some news that the fire is under control. it appears that the firing at the plant has ceased, but we are still under very dangerous situation. just to repeat what the us energy secretary has been saying — the department has activated its nuclear incident response team. how serious is that?

we hardly ever do this. the nest teams that are trained to respond to a nuclear incident any place in the world. but in ukraine, in a war zone? we're not going send nest into ukraine to deal with this. it's a reasonable position for the us to take, but it doesn't help the immediate situation. you've said that this is unprecedented, but given the facts of this invasion, is there anything that ukrainian technicians could have done to make the plant more safe given the fact that there were incoming tanks? no, there isn't. you're worried about two things here. this is a very large facility, i believe it has six nuclear realities. as you say, it is the largest nuclear reactor in europe. for the three reactors that are operating, which we are worried about, is that the assault would shut down the commander control, would breach the containment area

around the reactor, would cut off electricity, would cut off the plumbing. if any of those things would happen, you would lose the ability to control the reaction in the reactor, you would get an uncontrolled nuclear reaction that would result in a meltdown and an explosion like you saw in chernobyl. on the other hand, the three reactors that are already shut down, and if reports are accurate, they are shutting down the other operating reactors now, you've taken the fuel rods out and you've put them in cooling ponds, and that designed to keep these very, very hot, very radioactive fuel from interacting with each other. but again, if the electricity is cut off, damaged, the plumbing cut off and the pool water drained, again, you would get a super heating of these fuel rods, you would get an explosion, not a nuclear fusion explosion, but a thermal explosion that would spew highly radioactive material over tens of thousands of square kilometres. so having the reactors shut down doesn't guarantee that the emergency is over.

if the russians keep firing at these facilities or cut off the electricity or disable the commander control, you are still looking at a potential unprecedented nuclear disaster. ukrainian technicians clearly maintain the plant, but would they be capable of repairing it and doing emergency repairs or would technicians have to come from other countries? oh, no, if you've seen the hbo special in chernobyl, you have some idea of what we are talking about. i mean, once there is a meltdown, once the reaction is out of control, it's a highly radioactive environment, and people going in, trying to quell the blaze, trying to control it would be killed almost instantaneously by the radiation dosage they would be getting. so, no, once there is a breach, there's very little you can do about it except suicide—type safety measures. people would die trying to control the reaction.

elsewhere in ukraine, russian troops have been intensifying their attacks. 22 people were killed in an air strike at a residential area. there are fears of a humanitarian crisis in the southern port of mariupol. that is where civilians have been trapped by schelling. there are also reports of food shortages in the city of kherson where russian troops took control on wednesday. let's look at the map here. fighting, meanwhile, is continuing in the capital, kyiv, 2a kilometres from the capital's centre. my colleague clive myrie is in the area and his report contains distressing images. this is the city of chernihiv, 80 miles north of the capital, kyiv. and this is war. explosion this is a residential area. and here's another. russia's military did this to whole communities in syria,

as well as chechnya. their commanders have form. chernihiv lost 22 of its citizens in this attack. the governor says two schools were also hit. make no mistake about vladimir putin's desire to colonise this land. ukraine says russian targeting is indiscriminate. welcome to the town of borodyanka, population 12,500. parts of it a wasteland now of destruction in an increasingly dirty war. translation: god forbid, if we are no more, - then latvia, lithuania, estonia will be next, then moldova, georgia, poland and so on. they will march to the berlin wall, believe me. it's the same story

of destruction in southern ukraine. large parts of the port city of mariupol are being shelled. as russian forces tighten the noose, a humanitarian tragedy unfolds. the city's electricity supply has already been cut. and resistance, though noble, is futile in the city of kherson, conquered by russian tanks, the first major urban area to fall in this war. but there's no bigger prize than the capital, kyiv. an explosion overnight rocks the railway station. debris from a russian cruise missile shot out of the sky. it's unclear how many were injured. by day, the capital is being abandoned. these cars have been dumped outside the railway station as thousands flee. it is pretty much deserted here,

a couple of people out for a stroll in the snow. but this is a city that's so much on edge, and all the checkpoints that we've come across, the guards have come up to us, they've wanted to check our papers, wanted to check if we're filming them. there really is a sense of dread and unease here, which is, frankly, to be expected. and this is why — not farfrom kyiv, a column of heavy russian armour inches closer to the capital, waiting for vladimir putin's order to strike. president putin has defended his campaign. a televised address said that military operation was going to plan. mr putin also admitted some of his soldiers had been killed in the campaign and he stood for a moment's silence for russia's losses. he was generally defiant. he

accused ukraine of using civilians as human shields. he called them neo—nazis. translation: our soldiers and officers are fighting for| russia, for a peaceful life. for the citizens of the donbas. the denazification and demilitarisation of ukraine so that the anti—russia on our borders will not threaten us. the second round of talks held in neighbouring belarus have taken place despite failing to reach an agreement. both sides did agree on the need for humanitarian corridors in order to protect civilians. it could involve an agreement on roads leading out of populated areas. they came and shook hands. with their respective flags on the table, ukrainians and russians

sat down to talk this afternoon. no progress on ending president putin's war, but there was limited agreement on the possibility of setting up on the possibility of setting up humanitarian corridors to try to save the lives of civilians living in increasingly desperate conditions. translation: ., ., , translation: unfortunately we did not gather — translation: unfortunately we did not gather results _ translation: unfortunately we did not gather results we - translation: unfortunately we did not gather results we had - did not gather results we had expected. the only thing i can say is we discussed the humanitarian aspect in sufficient detail was many of the cities are now surrounded. there is a dramatic situation with food, medicines, the possibility of evacuation. earlier today, president macron of france took a call from vladimir putin was a french official say it lasted 90 minutes and left them fearing that worse was to come. it was said it was determined to reach his aims, but he felt the operation was going to plan. nato is continuing to beef up its forces in eastern europe as russia is subjected to ever

recover a western sanctions. so is there a way out for president putin now? yeah, there is a — president putin now? yeah, there is a way _ president putin now? yeah, there is a way out. - president putin now? yeah, there is a way out. he - president putin now? yeah, there is a way out. he can l president putin now? yeah, i there is a way out. he can stop what he is doing, he can withdraw his forces from russia and ukraine back to russia, he can tell belarus to stand down, and he can try and negotiate with the west about what he feels has been the wrong issues around people in the donbas or russian minorities. other problem is it is going to be pretty hard right now. im’ith problem is it is going to be pretty hard right now. with the lives of ukrainians, _ pretty hard right now. with the lives of ukrainians, russia - pretty hard right now. with the lives of ukrainians, russia is l lives of ukrainians, russia is writing a bloodied new chapter in europe's history, and western european countries have come together to respond. the prime minister of hungary who saw the crisis on the border todayis saw the crisis on the border today is to be president putin's closest european ally. we tried to provide the negotiations, because it is war. war can be stopped only by

negotiations and peace talks and ceasefire, but that depends on the russians and ukrainians, basically the russians. figs basically the russians. as russia continued to pound ukraine, the prospect of it holding you meaningful talks to end this war theme at the moment vanishingly small. the us turned up the pressure on russia, early imposing sanctions on at least eight oligarchs of president putin. those targeted include the owner of a giant mining company and also the kremlin�*s spokesman. president biden announced the move. in the state of the union address, i announced that the department ofjustice is going after the crimes of russian oligarchs, and the attorney general spoke to that earlier. and who line their pockets with russian people's money while ukraine and their people are hiding in subways from missiles that are being fired indiscriminately. today i announced that we are adding dozens of names to the list, including one of russia's wealthiest billionaires, and i'm banning travel to america by more than 50 russian oligarchs, their families

and close associates. stay with us here on bbc news. still to come: there is no slowing the wave of people fleeing the fighting. more than1 million people have now left ukraine. first, the plates slid gently off the restaurant tables. then suddenly, the tables, the chairs and people crashed sideways and downwards. it was just a matter of seconds as the ferry lurched onto her side. the hydrogen bomb on a remote pacific atoll. the americans had successfully tested a weapon whose explosive force dwarfed that of the bomb dropped on hiroshima. i had heard the news earlier, and so, my heart went bang, bang, bang! - the constitutional rights of these marchers are their rights as citizens

of the united states and they should be protected, even in the right to test them out, so that they don't get their heads broken and are sent to hospital. this religious controversy — i know you don't want to say too much about it — but does it worry you that it's going to boil up when you get the states? well, it worries me, yes, but i hope everything will be all right - in the end, as they say. this is bbc news. the headlines. president zelensky of ukraine has accused russia of nuclear terror after heavy weapons fired on his country's power station. the humanitarian crisis has gripped the port city of mariupol, as water supplies are cut off. give's now, former heavyweight boxing champion vitali klitschko, has warned many more people will die as a result of

a's invasion of his country, but ukrainians will never surrender. dozens of ordinary citizens have now taken up arms to defend the capital. orla guerin has been to meet some of them. the rush to get more defences in place. a democratic european capital waits for invaders at the gates. these are called hedgehogs and were designed to stop a tank. so, can ukrainian forces keep the russians out? "i don't know," says sergei. "i'm not a general. we'll try. that's why we're here. that's all i know. you need to ask the president." the last—minute preparations here include battlefield first aid. how to apply a tourniquet so you don't bleed out. at the city's edge, olga is sharing knowledge that might save lives.

how soon do you think it could be before there is real fighting here? unfortunately i think it's a few days, and we're afraid. but it's our town, it's our country, and we must save it, we must fight. olga, what were you doing before the invasion? are you a medic? no, i'm not medic. i just... gunfire. well, we'vejust heard some gunfire. the troops say that happens from time to time. it could be coming from russian forces or from russian saboteurs who are inside the city. and deep in a forest, more defences. felling pine trees to block the enemy's advance. shovels in hand, they dig in for a long fight. this could be a scene from the first or second world war, but it's now, today, 2022. well, there's a whole network of trenches being built here now. they tell us they have

to be ready and soon. they believe that russian forces could reach this position within a day or two. everyone here knows the russians have more firepower, but they say their morale is higher because they are defending their own soil. and the volunteers in the forest speak only of victory. "i think we'll win," this man says, "though it will be hard." "we will break them," his friend adds, "so their children and grandchildren will remember it forever."

back in the heart of the capital, independence square, cradle of the revolution in 2014. it's now deserted, and this city is a battleground in waiting. orla guerin, bbc news, kyiv. thousands of refugees are pushing west out of ukraine into neighbouring states. look at female peer. you will see the larger arrows indicate the biggest numbers people moving. poland has taken in the most. jules jones poland has taken in the most. julesjones is an american screenwriter living in warsaw, and is one of many people in poland offering shelter to refugees. as soon as i found there was a way to connect with people fleeing ukraine i immediately talked to my husband about it and we agreed to take people in. who have you got? have one family he just left this morning and went to a long—term apartment and tomorrow a new families on the bus on the way here and will arrive in the evening. you have any way of communicating? a shared language?

we use a bit of google translate and a little polish but my polish is not that good. we will make it work though! do you have space in your house? i'm actually in the room right now. this was the office but we cleared it out on the day that we decided we would do this and friends donated furniture and we got it all set up so it would be a comfortable place for people to rest and figure out what to do next. tell me about the reaction of friends and family then? it was interesting. as soon as they realised there was something that could be done, they wanted to be involved and help. i've had an outpouring of people bringing me things that we needed to make a comfortable home, donating money forfood and supplies for the people. everyone wants to do what they can to contribute. what is the thing they need the most apart

from a warm bed? i don't know. i thinkjust acceptance and time and stability. just a feeling that they are safe and do not have to worry where they are going or if their kids understand what is going on. that their children feel safe and feel this is less of a horror and more of a visit, i guess. i understand you have got really young kids. what you want them to learn from this experience when they see new people coming into your house? i think it's a really great experience for my children. we didn't quite explain at the beginning what was going on but my five—year—old is very perceptive and she wanted to know why they did not have anything. what they didn't have any toys, why they didn't have a lot of possessions and why they were not at home, and she figured it out.

she was very excited for her new friends and their three—year—old, what she can understand is that there is a new girl here who also love the same cartoons she does, likes the same goals, and so for them, just a chance to take it naturally, that you can accept people with open arms even if you cannot communicate with words, you can find common ground and be loving. thank you so much forjoining us. workers at the key of zoo which was due to shut down due to the invasion have moved into look after the animals around the clock. —— kyiv zoo. residents of the zoo include this elephant, and tony, whom we will see in a bed, the only gorilla in ukraine. they are all doing well despite the shelling and the metal strikes, which are happening nearby. i think that is the gorilla,

tony. ok. more on all of our stories on our website and on twitter. hello there. cloud and outbreaks of rain are continuing to move very slowly eastwards. we should have more sunshine around across the uk this weekend, but on thursday, the best of the sunshine was across northern ireland. highest temperatures, though, were in the south—east of england — 1a degrees — ahead of that band of thicker cloud, which is taking that rain very slowly eastwards. there are some breaks in the cloud coming in from the west, a few showers around as well, but temperatures early morning could be close to freezing perhaps in northern ireland and western parts of scotland. further east, it's milder, but it is wetter. we've got cloud and rain from the word go. and for a while in the morning, that rain could be on the heavy side before it pulls away from much of eastern scotland and eventually from the north—east of england. we keep some rain, though, further south

across eastern england. further west, though, we're into that brighter sky, some sunshine and maybe one or two showers for northern ireland, western scotland, wales and western england. and these areas on the whole, a little bit milder, i think, on friday. still quite cold, though, for eastern scotland and the north—east of england. improvements, though, this weekend. more sunshine to come for scotland and northern ireland, and we should slowly see the weather improving across england and wales as that rain finally moves away. but we start the weekend cold in scotland and northern ireland, a slight frost here. there's even a risk of temperatures close to freezing in the south—west of england and south wales. further east, though, we've still got that band of cloud and rain. and that will tend to sink its way southwards and westwards, taking some of that damp weather towards the south—west of england, but allowing more sunshine in wales now, and the north of england, together with sunshine in scotland and northern ireland. and in the sunshine, temperatures 8, 9 degrees, so a milder day for eastern scotland and the north—east of england. second half of the weekend

sees the back of this weather front at long last. looks like it is going to be fading away a little more quickly now as that area of high pressure builds down from the north. so, the rain gets squeezed out. if there is any rain, it's really down through the english channel. a dry picture, generally, i think, on sunday. more sunshine to come across england and wales, certainly some brighter skies here, and we continue to see the sunshine after a cold start in scotland and northern ireland. still not particularly warm for the time of year. temperatures only around 8 or 9 degrees. high pressure builds in this weekend, and then it starts to slip away to the east of the uk, allowing a stronger wind to pick up, but it looks like all these weather fronts and rain are going to stay away towards the west.

this is bbc news. the headlines: ukraine's president has accused russia of nuclear terror after reportedly combining the biggest new power station. —— reportedly bombarding. officials say that safety workers have no access to the building to tackle a fire which broke out in a training laboratory. the international atomic energy agency is that the equipment in the plant is still functioning. the russian bombardment of cities across ukraine is intensifying. air strikes have taken place north of kyiv. president putin has claimed his military campaign is on track. ukraine's president has appealed for further military aid. washington is turning up the pressure, imposing sanctions on oligarchs and associates of the russian leader. the uk's also taken further action against two oligarchs, the former russian deputy and associates.