this is bbc news. i'm ben boulos, with the latest headlines for viewers in the uk, and around the world. the world's richest man, elon musk, buys twitter for $41; billion, putting free speech at the forefront of his plans, but there are fears over what shape this could take. no matter who owns or runs twitter, the president has long been concerned about the power of large social media platforms. the un secretary general antonio guterres meets vladimir putin in moscow later, as ukraine asks him to initiate a humanitarian corridor for civilians trapped in a steel plant in the city of mariupol. in russia, there are two huge explosions at an oil depot, not far from the border, with ukraine — the russian foreign minister suggests the conflict could lead

to a third world war. the us says it's "deeply troubled" by the conviction in turkey of activist osman kavala, after he was sentenced to life in prison without parole, on charges of attempting to overthrow the government. for the first time, black women artists from britain and the united states win awards at the prestigious venice biennale. hello, and welcome to the programme. the tech—tycoon, elon musk, has struck a deal, worth around $41; billion, to buy twitter. when he assumes ownership at the end of the year, mr musk, who's the world's richest man, will control a social network with 300 million users, including many world leaders. he's described himself as a free—speech absolutist, leading civil rights groups to warn against twitter

becoming a breeding ground for hate speech. our technology correspondent james clayton reports from san francisco. elon musk usually tweets cryptic messages, but there was nothing cryptic about his reaction to the news that twitter had accepted his offer. but people here in silicon valley are rubbing their eyes with disbelief. the world's richest man, now the owner of one of the most influential social media platforms. twitter isn't the most used social media site in the world, but it is hugely influential. world leaders likejoe biden, narendra modi, emmanuel macron and borisjohnson are all on it. when it comes to news generation, twitter has no comparison.

but for years, people, particularly on the right, have said twitter stifles free speech. yet twitter has been criticised, particularly from the right, that it's stifling free speech. donald trump's sensational lifetime ban from the platform is held up as a seminal moment, a sitting president's megaphone removed by big tech. elon musk says he wants to bring back free speech to the platform. the problem is, though, that unfettered free speech can get very ugly, very quickly when it comes to social media. no matter who owns or runs twitter, the president has long been concerned about the power of large social media platforms, the power they have over our everyday lives, he has long argued that tech platforms must be held accountable for the harms they cause. mr musk will now have to deal with movements like qanon, disinformation campaigns, and hate speech. the danger is twitter, without moderation, becomes poisonous. but for now, elon musk is rejoicing. twitter is now his

personal plaything. he's the new undisputed king of twitter. james clayton, bbc news, san francisco. taylor lorenz is a columnist at the washington post, covering social media and internet culture. taylor, in your view, taylor, in yourview, is taylor, in your view, is this a victory, this move a victory for free speech, or is it a victory for proliferation of hate speech? it victory for proliferation of hate speech?— victory for proliferation of hate speech? it is absolutely not a victory _ hate speech? it is absolutely not a victory for _ hate speech? it is absolutely not a victory for free - hate speech? it is absolutely not a victory for free speech. i mean, the idea that elon musk, who constantly has silenced critics, fired people for speaking out, some sort of champion free speech, is quite shocking, it is really not in line with his track record at all, and i think when we think about free speech, we have to think about whose speech is free, right? a lot of times, these hate groups will attack

and harass users of marginalised backgrounds of the platform, thereby silencing them and censoring them. if you allow bad actors like that to run rampant on the platform you have to think about who that was silence, so these are all things he will have to wait, and he has not had a super nuanced view of in the parser will be interesting to see. were so this will be viewed by interest of people who have a financial stake in twitter, shareholders and the like. for most of the rest of the audience, twitter users, what difference will they see, if any, do you think? i difference will they see, if any, do you think?- any, do you think? i think elon has shown _ any, do you think? i think elon has shown he _ any, do you think? i think elon has shown he is _ any, do you think? i think elon has shown he is a _ any, do you think? i think elon has shown he is a bit _ any, do you think? i think elon has shown he is a bit of- any, do you think? i think elon has shown he is a bit of a - has shown he is a bit of a chaos agent, not afraid to shake things up. he has only done a few twitter polls, about editing tweets, and i think it is clear he will have an impact on the product and twitter will change in that many ways. that said, i don't think his world view is that different from jack dorsey, who led the

company for many years, it seems like they have similar philosophies, so we will see how involved he is on the day—to—day. how involved he is on the day-to-day-_ how involved he is on the day-to-day. given it has set out his view _ day-to-day. given it has set out his view of _ day-to-day. given it has set out his view of being - day-to-day. given it has set out his view of being an - out his view of being an absolutist when it comes to free speech, you think the ground has been set for a conflict with regulators in the months ahead?— conflict with regulators in the months ahead? yes, i think he is not even _ months ahead? yes, i think he is not even an _ months ahead? yes, i think he is not even an absolutist - is not even an absolutist remotely even when it comes to his track record, so will see if he abides by that and what those consequences are. he decries spam bots, and crypto spam bots, you cannot clean up spam bots, you cannot clean up spam on a platform unless you are moderating in some capacity, so i think absolutely regulators will be watching. i think the fact that the world's richest man can buy this incredibly influential platform, when it comes to news and media and communication, is definitely eye—catching in that way. and he will have to be very careful about his next steps. very careful about his next ste s. ., . very careful about his next stes. ., . ., . ., very careful about his next stes. ., ., ., steps. from a financial point of view. _ steps. from a financial point of view. do _ steps. from a financial point of view, do you _ steps. from a financial point of view, do you think - steps. from a financial point of view, do you think you - steps. from a financial point| of view, do you think you will be able to make twitter

profitable at last? well, twitter has _ profitable at last? well, twitter has struggled i profitable at last? well, | twitter has struggled for profitable at last? well, - twitter has struggled for years to really capture the value that it has in monetary terms. it has this enormous cultural relevance but it is very hard to monetise full stop they have rolled out twitter blue and certain subscription models, assuming he will continue with those efforts. we will see. some of his companies have been successful, some have notoriously not. he makes a lot of grand plans and doesn't always follow through on that. so i think we will see, he no longer has to answer to the public, it is a private company searches his money to lose igas. ., ~' , ., searches his money to lose igas. ., ~' ~ searches his money to lose igas. . ~' , ., ~ . searches his money to lose igas. . ~ ~ ., ., igas. thank you. we will have a lot more analysis _ igas. thank you. we will have a lot more analysis of _ igas. thank you. we will have a lot more analysis of that - igas. thank you. we will have a lot more analysis of that $44 i lot more analysis of that $41; billion takeover deal in the business news. that is coming up business news. that is coming up in about 20 minutes. stay with me for that. in the

meantime, let's turn our attention to the other day's news. the other day's news. the secretary general of the united nations is due to meet vladimir putin in moscow later. antonio guterres is then expected to travel to kyiv to hold talks with the ukrainian president on thursday. talks are expected to focus on the city of mariupol, where, despite declaring a victory, russian troops have failed to take the azovstal steelworks. ukraine has asked mr guterres to initiate and guarantee a humanitarian corridor, to allow civilians sheltering inside the plant a safe route out. a corridor, proposed by russia on monday, failed, after ukraine said it had not been consulted, and attacks on the steelworks continued, despite moscow's promise of a ceasefire. the russian foreign minister, sergei lavrov, has again suggested there's a danger of the ukraine conflict leading to a third world war — but he said he expected it to end with a negotiated peace agreement. he accused nato of engaging in a proxy war with moscow. meanwhile, russia says it will investigate the cause of a large fire that erupted at an oil storage facility in the city of bryansk,

where it appears there were two explosions. 0ur russia editor, steve rosenberg, sent this report from the scene. caught on cctv, the prelude to an inferno. the russian fuel depot was engulfed in a fireball. flames lit up the night sky over bryansk. then, over to the right, you can see a second explosion. the border with ukraine is less than 100 miles from here. so, was this the result of a ukrainian strike to disrupt logistics for russia's military offensive? was it sabotage? neither moscow nor kyiv are saying. all day, plumes of thick, black smoke hung over the city, making bryansk feel like a war zone. "this never happened before," she says.

"at 3am, we heard explosions. "we were amazed". "i don't know what this is," he says. "is it war here? "i suppose we're on the front line. "i wonder if ukraine did this". we've seen something similar, early this month, in belgorod. russia claimed that ukrainian helicopter gunships had opened fire. kyiv wouldn't confirm it. whatever the cause of today's fire, it's sparked concern in this city. when the kremlin launched its so—called special military operation two months ago, for many here, it was a case of "out of sight, out of mind". this was a conflict playing out on tv screens. but that's changing, and, for many russians now, hostilities are starting

to feel much closer to home. back in moscow, president putin accused the west of prolonging hostilities in ukraine. translation: to our surprise, senior diplomats in europe - and the us are ordering their client state ukraine to do everything possible to achieve victory on the battlefield. this is impossible, so now they plan to destroy russia from within. vladimir putin claims he sent his troops into ukraine to bring russians security, but there's little sign of that. steve rosenberg, bbc news, bryansk. let's get some of the day's other news. north korea's leader, kimjong—un, has made a defiant speech at a military parade, vowing to ramp up the country's nuclear arsenal. the parade, to mark the founding anniversary of the country's armed forces, also saw several banned intercontinental ballistic missiles displayed. in march, north korea tested an icbm for the first time since 2017.

the authorities in beijing have stepped up mass coronavirus testing to include most of the 21 million residents, fears of a lockdown has prompted panic—buying of goods in china's capital, which reported 33 new coronavirus cases on tuesday. that contrasts with the 52 deaths and 16,000 total cases recorded in shanghai. an appeals court in texas has halted the execution of a woman convicted of killing her two—year—old daughter in 2007. melissa lucio was scheduled to die on wednesday. the court granted a stay of execution so that prosecutors could reconsider new evidence in the case. a capsule carrying three businessmen and a former nasa astronaut, who took part in a landmark commercial space mission, has splashed down off

the coast of florida. they took part in a landmark commercial space mission. during their trip to the international space station, the crew carried out a series of scientific experiments. each of them is thought to have paid more than $50 million for their trip. ajudge in new york has found donald trump in contempt of court for failing to provide documents investigation into his business practices. the former us president has been ordered to pay a fine of $10,000 a day until he complies. the new york attorney general has been probing mr trump's business practices for two years. mr trump's lawyer said she would appeal the ruling. a partner in the new york law firm buckley llp, daniel r alonso, gave his reaction to the ruling. subpoenas are not optional, court orders are not optional, people comply with them every single day. it is very unusual for somebody to just sort of say, "look, i'm just not going to comply with this", or tojust keep arguing, even after they've been ordered.

and the government — in this case, the attorney general, just got fed up. so he's got to comply. everyone else has to do it. there is no loophole forformer presidents. stay with us on bbc news, still to come: the winning black female artists at the centre of this year's venice art biennale. nothing, it seemed, was too big to withstand the force of the tornado. the extent of the devastation will lead to renewed calls for government help to build better housing. internationally, there have already been protests. sweden says it received no warning of the accident. indeed, the russians at first denied anything had gone wrong. only when radioactivity levels began to increase outside russia were they forced

to admit the accident. for the mujahideen, the mood here is of great celebration. this is the end of a 12—year war for them. they've taken the capital, which they've been fighting for for so long. it was seven o'clock - in the morning on the day when power began to pass from the minority to the majority. - when africa, after 300 years, reclaimed its last white colony. - this is bbc news, the latest headlines: the world's richest man, elon musk, buys twitter for $41; billion, putting free speech at the forefront of his plans. but there are fears over what shape this could take. the un secretary general antonio guterres meets vladimir putin in moscow later

as ukraine asks him to initiate a humanitarian corridor for civilians trapped in a steel plant in the city of mariupol. the united states has said it is "deeply troubled" by the conviction of the turkish activist, 0sman kavala. he was sentenced to life in prison without parole in turkey after being found guilty of attempting to overthrow the government. let's get more detail from our news reporter, mark lobel. how significant is this verdict? this has added fuel to the fears about the independence of the judiciary fears about the independence of thejudiciary in turkey, fears about the independence of the judiciary in turkey, since 2016 when there was the failed coup against the president we saw the purge ofjudges, saw a brain drain and those judges that remained in the judiciary are paralysed by a climate off according to analysts. this is what one campaign had to say outside that court in istanbul.

deeply shocking and i think a very defiant decision which, of course, does not come from this court, it comes from the palace, and this has been a political trial from start to finish. it is a sham trial, we call it, because there is no evidence. it all began with the turkish government concerned with anti—government protesting in 2015 — anti-government protesting in 2013. ,, . , ., , 2013. since then trying to pin the blame — 2013. since then trying to pin the blame on _ 2013. since then trying to pin the blame on civil— 2013. since then trying to pin the blame on civil society - the blame on civil society saying they have been funding and overthrow of the government, saying they are agents of the hungarian millionaire george soros, but it came down to monday in istanbul in court with seven defendants got 80 years each for this attempted overthrow, a 64—year—old philanthropist, 0smond kabbalah who had been detained already for four and a half years without conviction facing life in prison without parole. he says the judiciary has been used as an act of

assassination against him. as their international condemnation, you bet. six months ago a letter from ten western diplomats asking for his release, they were nearly expeued his release, they were nearly expelled from the country, america said it is deeply troubled and disappointed, the european human rights body of which turkey is a member said there is a lack of evidence calling for his release, turkey risking being kicked out of that. turkey has worked with the international community in the international community in the ukraine and russia wore they say allegations against him are politically motivated. for many people this was a litmus test of the role of war in turkey, and for many people, it's been awful results. let's get a full round—up of all the sports news now. hello.

it's champions league semi final time on tuesday and there's a titanic clash to tuck into as premier league leaders manchester city host la liga leaders real madrid in the first leg. pep guardiola's side lost 1—0 to chelsea in their first champions league final last season while real have been european champions 13 times. guardiola will make late decisions on the fitness of england defenders john stones and kyle walker, who are both injury doubts. city manager says they will need "two exceptional games" to overcome their spanish opponents. we now try to be ourselves, we have two do exceptional games to reach the final. hopefully, we can do it. be ourselves, and it is unnecessary to say how much we respect real madrid, how good they are, and that's all. this is the third time in seven seasons that city have reached the last four, however real madrid are perennial diners at the top table, they're in the semi—finals for the 10th occasion in 12 years. and while they're on the cusp of winning la liga, which means carlo ancelotti

will be the first manager to win each of the five strongest domestic leagues in europe, so england, spain, germany, italy and france, he feels his side have not been expected to reach this stage of the competition. we are very close to playing another final of the most important competition in the world. we are worried because we are facing a very strong team. we are used to this because in the champions league we face very strong opposition in the round of 16, quarter—finals and now semis, with all of them being among the favourites to win the tournament. we played against them and things went our way, so we will keep fighting. to the portuguese primera liga where braga delayed porto's chances of clinching the league title as they beat the table toppers 1—0 on monday. ricardo horta scoring the only goal of the game for the home side just after half time. incredibly, that's porto's first league defeat for 18 months, going back to october 2020. porto have a six—point lead at the top of the table with three matches left.

to the world snooker championship, and there's no greater achievement in the sport than a 147 break, and before monday, there'd only been eleven made at the crucible in its history. so what a moment for australia's neil robertson, applause. the pre—tournament favourite, who sent the crowd wild with just the twelfth maximum in the history of this sport's iconic venue. it came at a crucial time in an epic second round match too, with robertson fighting back against england's jack lisowski. he had been 9—7 down at the start of the evening session, and this match going on late into the night in the united kingdom. so robertson, despite making that 147, ended up losing the match and is out. a gutsy performance from lisowski, who won in an final frame decider, 13—12 which sent him into the quarterfinals,

which won't be an easy one. it's the small matter of a match against four—time champion john higgins. the 2019 winnerjudd trump was also involved in a long, late night tussle. his match with anthony mcgill also going right down to the wire, with trump eventually sealing it 13 frames to 11. he'll face stuart bingham, the 2015 winner, in the quarter finals. you can get all the latest sports news at our website — that's bbc.com/sport. but from me, and the rest of the sport team, goodbye. the venice art biennale opened over the weekend, and the british artist, sonia boyce has won the top prize, the so—called golden lion. she'd already made history as the first black woman to represent britain at the international art exhibition. the other golden lion for the best artist was won by another black artist, america's simone leigh. here's our culture editor,

katie razzall. the british pavilion at the venice art biennale has been transformed to the sound of five black female musicians. it's a hugely noisy, but hopefully joyously noisy experience. sonia boyce's work here, called feeling her way, is the latest stage in a wider project that tells the stories of black women singers and musicians. you are the first black female artist to ever represent britain. i wonder what you feel about that. um, i mean, of course it's an enormous accolade. but i also think, why has it taken so long? i mean, there are so many brilliant british female black artists out there. it should have happened before now. it's her time in the sun now. with a golden lion for the show, she's joined the likes of other famous british names, bridget riley and henry moore amongst them, to the very top biennale prize. boyce had this message. there's a longer arc of people that we need

to keep saying, they're here. for more than a century, the world's most high profile art exhibition has centred around men. not this year. close to sonia boyce's pavilion, america's has a new temporary thatched roof, and an exhibition courtesy of simone leigh, the first black woman to represent the us here. they wanted to start this part of the show with this monumental artwork. simone leigh won the other golden lion prize for this 16—foot bronze sculpture at the central biennale show, curated by cecilia alemani. of the 213 artists featured in what's called the milk of dreams, between 80% and 90% are female. i wanted to give the stage and the platform to many amazing, wonderful artists who also happen to be women. and why has it taken so long, do you think? because we still live in a very sexist society, and it's very, very hard to advance.

advance is happening in scotland's exhibition. this tapestry looks at slavery and the stories we're told. the artist, alberta whittle, is the first black woman to represent scotland in venice. i think the world's more ready to accept women artists, possibly. black women artists, i don't know. i'd like it if people weren't so scared to work with ideas of race or to kind of open up these conversations. but change is afoot here, certainly when it comes to whose art gets a place on the wall. katie razzall, bbc news, venice. stars of the popular british television series downton abbey have hit the red carpet for the the world premiere of the franchise's latest film, "a new era", which follows the crawley family as they travel to the south of france to visit a newly inherited villa. hugh bonneville, who plays the earl of grantham, said audiences should come along to the cinema and just sit back and have fun!

you can reach me on twitter — i'm @benmboulos. business news coming up. hello. if it's rain you're after, you won't find any substantial amounts in this forecast. we were on monday teased by a few showers out there that only produced a few millimetres of rain here and there and they are not a sign of things to come. this weak weather front in scotland in northern england will squeeze out a little light and patchy rain on tuesday. but this is the main weatherfeature building in for the rest of the week and looks like for the rest of the month too. high pressure right across us, keeping things largely dry and settled, with a chance, though, it's on the cool side out there. a the touch of frost over the next few mornings. for tuesday mornings, across parts of southern scotland, northern and eastern england. many starting with sunshine but some thicker cloud across parts of scotland, running down into northern england, will produce a little light and patchy rain,

not amounting to very much. the far northeast of scotland brightens up a touch. northern ireland, wales, the midlands, east anglia and southern england, a lot of early sunshine, some cloud building, the chance of an isolated shower — that's all it's going to be. these areas seeing some of the higher temperatures, warmest near 17 degrees, but feeling quite cold through eastern scotland and northeast england, especially with this onshore breeze. any showers that have developed along with the cloud will melt away overnight and into wednesday morning. we keep some cloud though across eastern—most parts here. the chance again of a touch of frost looks to be on wednesday in parts of scotland and northern england. then on wednesday, it does look as if that area of high pressure moves right in to be a mainly dry day. where you start with cloud in the east, it mayjust thin and break in places. where you start elsewhere was sunshine, some clouds going to build, but we'll continue to see some sunny spells, and there'll be a range of temperatures, from the cooler north sea coast, to something closer towards the mid—teens in the warmer spots elsewhere.

by then on thursday morning, could be quite a bit of cloud through wales, in much of england, although there's a hint of something sunnier towards southern england and south wales, although breezier as well. just may lift the temperature a little bit higher than it's been. a few sunny spells still around in scotland and northern ireland. that area of high pressure stays with us into the weekend. there is a chance on saturday, perhaps seeing a little patch of rain towards northern ireland and scotland. not set in stone. it is the exception to the otherwise largely dry theme. bye—bye.

this is bbc news, with the latest business headlines for viewers in the uk, and around the world. the world's richest man buys twitter, and promises to make it better. we take a look at elon musk�*s take—over of the social media giant. profits at hsbc drops 27%, mainly due to a slowdown in hong kong. an all—american pick—up truck goes electric. we take a look at how ford aims to convert skeptic drivers to its latest e—vehicle. and how to grow "green cities". we visit the floriade exhibition in the netherlands, where more than a0 countries are showing how it can be done.