the headlines at 11pm: the white house shows support for britain, after theresa may announcs sanctions against russia. and the scientist stephen hawking, who achieved fame with his theories of the universe, has died aged 76. tens of thousands of students have walked out of classrooms across the us to call for tighter gun controls, a month after a shooting at a school in florida. and on newsnight, russia says its relations with britain are at a temperature of —23, but that it's not afraid of cold weather. we'll ask if britain's measures will have an effect. and whetherjeremy corbyn judged it right, in his response to the prime minister. good evening and welcome to bbc news. britain is expelling twenty three russian diplomats after moscow

refused to explain how a military grade nerve agent was used on a former spy in salisbury. it's the biggest such expulsion for more than 30 years. the prime minister told parliament that the "undeclared intelligence officers" have just one week to leave. the uk has also cut off all high level contacts with russia and announced that government ministers and members of the royal family will not attend the world cup. here's our political editor, laura kuenssberg. the midnight deadline came and went, leaving a morning with no new a nswe i’s. leaving a morning with no new answers. theresa may when prepared to prime minister's questions, ready to prime minister's questions, ready to announce the biggest diplomatic action against russia since the cold

war. they have treated the use of a military grade nerve agent in europe with sarcasm, contempt, and defiance. . there is no alternative conclusion other than the russian state was culpable for the attempted murder of sergei skripal and his daughter. 50 the uk will retaliate. the united kingdom will now expel 23 russian diplomats who have been identified as undeclared intelligence officers. they have just one week to leave. this was notjust an act of attempted murder in salisbury, norjust an act against uk. it is an affront to the prohibition on the use of chemical weapons, and it is an affront to the rules—based system, on which we and our international partners depend. so 23 diplomats suspected of being spies have seven days to leave, all high—level contact

between the uk and russia is also being suspended, and no minister or member of the royal family will go to the world cup. and some russian state assets could be frozen, with possible new laws to crack down on hostile states. in a tense house of commons, jeremy corbyn was not quite ready to accept the culpability of the russian state. our response must be both decisive and proportionate, and based on clear evidence. but listen to rising anger, asjeremy corbyn turns some of his fire on the tories. it is, as we on these benches have expressed before, a matter of huge regret that our country's diplomatic capacity as been stripped back with cuts of 25% in the last five years. it is tradition for the two main parties to stick together on foreign policy. not these two. this is not a question of our diplomacy, of what diplomatic

support we have around the world. this is a question of the culpability of the russian state, for an act on our soil. fever rose. their continued disregard for the rule of law and for human rights must be met with unequivocal condemnation. look, tories cheering labour backbenchers. jeremy corbyn‘s team, arms folded. the russian government has behaved with arrogance, with inhumanity and with contempt. anger displayed in westminster that this is happening on british streets. in dorset today, the lorry that removed the skripals' car, seized. in salisbury, the bench where father and daughter were found, still sealed off. while the prime minister makes her opening moves in a diplomatic tangle that could last. laura kuenssberg, there.

in the past few minutes speaking at an emergency session of the united nations security counsel tonight, the united states offered full support to the united kingdom. let me make one thing clear from the very beginning: the united states stands in absolute solidarity with great britain. the united states believes that russia is responsible for the attack on two people in the united kingdom, it using a military grade nerve agent. dozens of civilians and first responders were also exposed. police officer nick bailey was the first to arrive on the scene. and remains hospitalised in serious condition. our thoughts and prayers go out to be victims of this approach is —— atrocious crime. tonight russia has again denied being involved and has demanded to see material proof of a russian link to the nerve agent

used in salisbury. our moscow correspondent, steve rosenberg, reports. in russia, at least the weather is showing signs of a thaw. after long winter, moscow is melting. but in uk russia relations, you can feel the chill. britain's expulsion of russian diplomats has sparked anger with theresa may. prime minister may is destroying international law, and is destroying international relationship. of course, it is the end of her career. it's the end. it's a show. that was a political show. and this is not, it's not serious, it's not for the serious politician. and this was the show on russian tv, while mrs may was announcing sanctions. commenting live, andrei lugavoy, the man britain believes poisoned former russian agent alexander litvinenko in 2006. moscow refuses to extradite him. as for kremlin funded english—language channel rt,

theresa may has left it up to uk regulator ofcom to decide whether it can keep its uk licence. what do you think the chances are of rt being censored in the uk? i hope rt is not censored in the uk, because i really would not like british media, including you, you are a very nice man, a gentleman, to be expelled from russia, which is exactly what i believe will happen if rt is censored in the uk. the british government wanted to send a strong message today to moscow. but that message has been dismissed here as nothing more than a provocation, and it plays into the narrative which the kremlin has been creating for some time, that the west is against russia. the man who styles himself as the defender of russia came to crimea today, territory vladimir putin

annexed from ukraine. with an election in russia in four days' time, uk sanctions may help the kremlin leader rally support. tonight, moscow is showing no signs of buckling under british pressure. russia is promising retaliation soon. steve rosenberg, bbc news, moscow. meanwhile the police and army have sealed off areas of the north dorset town of gillingham as part of the investigation. a cordon was put in place around a truck thought to have recovered mr skripal‘s car from salisbury — about 20 miles from gillingham. two large military trucks

were present and two police tents had been set up with people putting on protective suits inside. tributes have poured in from all over the world for professor stephen hawking — one of the greatest scientists of modern times — who died this morning at the age of 76. he was diagnosed with a rare form of motor neurone disease when he was 22 and told he only had a few years to live. but he defied all expectations and went on to become one of the most famous physicists in the world thanks to his studies on black holes and relativity. earlier we heard from professor lisa randall, an expert in string theory at harvard university. she said he was a larger than life character anyone who meets in, it is an incredible thing. you don't necessarily expect to meet somebody who is engaging, has a sense of humour, and is really sure. of course, the process of speaking ta kes a course, the process of speaking takes a long time, but it was always worth it. you know? i was fortunate that i went to a conference where i was actually late and 70 pulled me aside, and said he saved me a seat. he was interested in the research that i had done at the time. —— somebody. i sat at the table with

somebody. i sat at the table with some people, and we talked among ourselves. when he spoke, we were dropping citizen. i got to see how he functioned and worked. i met him at another conference later. —— we dropped things and listened. he was a larger—than—life dropped things and listened. he was a la rger—than—life personality. dropped things and listened. he was a larger—than—life personality. it was interesting. when it came to his work, people talked about him inspiring generations to come. what is it— inspiring generations to come. what is it — for those who don't study physics and don't understand the detail that he did, what will he lead to future generations? there is lots of technical work, but i think one of the reasons that his work was so one of the reasons that his work was so important was that he said something so magnificent, amongst his many other acknowledgements, but he was famous for saying that black holes decay. before that, it was thought that they were classical objects that lasted forever. but because of quantum mechanical effects, they will decay. that might not sound like a big deal in some

ways. many objects get formed the decay. but things get destroyed in the process of going into a black hole. so it gives rise to fundamental questions about what happens to information, and how does causality get maintained? these are deep and important questions. really it has been decades that people have been thinking about these problems. students across the united states have walked out of their classrooms today to demand tighter gun safety laws. they staged a seventeen—minute protest to represent the seventeen people who were killed in the florida school shooting exactly a month ago. here's our north america editorjon sopel. all chant: hey-hey, ho-ho, the nra has got to go! the last time we saw children pouring out of school, it was with their hands up in terror after the florida shooting. today they came out across america, but this time with fists clenched, demanding change on gun control. what do we want?! all chant: gun control!

when do we want it?! all chant: now! in washington at ten o'clock on a bracing cold morning, with their backs turned on the white house, these students fell silent for 17 minutes — a minute for each of the people who died at the marjory stoneman douglas school in florida last month. cheering. there's no doubting the extraordinary success these young people have had in changing the whole terms of debate on the subject of gun control in america. their problem is that the man who lives on the other side of that fence seems to have got cold feet. all chant: hey-hey, ho-ho, the nra has got to go! when donald trump met youngsters from the florida school at the white house, he seemed to offer his support for tougher gun control measures, like raising to 2! the age at which you can buy a rifle. and he later chided lawmakers for being frightened of the national rifle association. some of you people are petrified of the nra. you can't be petrified. but he's now backed off those proposals and so young people are intensifying their campaign. we want them to pass common—sense gun laws.

common—sense gun laws. we want to see a ban on assault rifles. background checks, everything. we don't want to be scared in school. it should be our safest institution. we are tired of being scared. we want actual change. we want it to happen with this protest. this is what democracy looks like! this is a curtain raiser to a mass demonstration in washington in ten days' time. they are a long way from getting what they want, but the power of youth protest has got them further than anyone could have imagined. and they are not in any mood to surrender. all chant: never again! jon sopel, bbc news, washington. the comedian and television

presenterjim bowen has died at the age of 80. he presented the popular itv quiz show, bullseye, which combined darts ability and general knowledge. for 11! years the show ran, but ended in 1995. he knowledge. for 1a years the show ran, but ended in 1995. he had been in ill health for several years. that's a summary of the news, newsday is coming up at midnight — now on bbc news it's time for newsnight with evan davis. mr speaker, there is no alternative conclusion other than that the russian state was culpable for the attempted murder of mr skripal and his daughter. relations between britain and russia are put into a deep freeze. russia responds by saying — we are used to cold weather. rarely does britain find itself at the centre of such a major diplomatic struggle. we'll hear from the security minister. and did jeremy corbyn judge it right in his response? some of his own mps don't think so. the shadow security minister will explain labour's position. brexit secretary david davis has been travelling the continent today —

and seeming to make brexit concessions to the europeans, exclusively to nick watt. i'm not bothered too much about the question of whether it's christmas 2020 all easter 2021. so if it means christmas 2020, you'd go for that? i'd go for that. also tonight, we're with stephen hawking's famous collaborator, the mathematician sir roger penrose. and angela merkel has been sworn in for her fourth term in office — but germany now has to contemplate political life without her. gabriel gatehouse is in the rhineland.