this is bbc world news, i'm duncan golestani. our top stories: international condemnation after saudi arabia admits the missing journalist jamal khashoggi was killed in its consulate in turkey. president trump says the us plans to withdraw from a key nuclear weapons agreement with russia, accusing moscow of violating the deal. hundreds of central american migrants are trying to cross into mexico after police blocked their march towards the united states. and millions of afghans vote in parliamentary elections which have been marred by violence. welcome to bbc news. turkey says it will reveal all the details about the killing of journalist jamal khashoggi

after saudi arabia admitted for the first time he had been killed in its consulate in istanbul. our diplomatic affairs correspondent james robbins reports. after 2.5 weeks of denial, saudi arabia is changing its story. state tv announced the admission that jamal khashoggi was killed by its officials. translation: the discussions that took place between him and the individuals that met with him during his presence in the saudi consulate in istanbul led to an argument and fist fight with jamal khashoggi, which led to his death. that is also the admission of a big saudi lie — previous insistence that the journalist didn't just walk into the consulate, he left safely too. many believe the killing could only have happened with the permission of saudi crown prince mohammad bin salman, and that the new story of a fight,

rather than premeditated murder, is designed to shield him. president trump, who has been torn between criticising the saudis and protecting business with them, now appears willing to accept the new saudi explanation as credible. they've arrested, just for the people at the table, a large number of people having to do with the event that took place in turkey in the consulate, the saudi consulate, and... it's a big first step. it's only a first step but it's a big first step. do you consider it credible, their explanation for it? i do, i do. but many disagree, including within his own republican party. senator lindsey graham said... so will the saudi admissions and arrests solve britain's dilemma — how to respond? hardly. the government is committed to uphold a world order based on rules, but it doesn't

want to inflict too much damage on saudi partnerships it values enormously. the foreign office confined initial reaction to a short statement. it begins... but don't expect action before turkey publishes some of its evidence. turkish officials have suggested a grotesque sequence of torture and killing inside the saudi consulate. turkey is promising to reveal all its findings. james robbins, bbc news. earlier i spoke to safa al ahmad, saudi journalist and filmmaker, and asked her if she expected the saudi explanation that had emerged. no, not at all, actually. all the millions in pr that the saudi government has spent for years on such an occasion, and this is all they can come up with, is actually quite sad.

what do you think explains it? does it bely the fact that there is panic in riyadh? i'm sure there's panic, but there's also a high degree of hubris on the saudi government's side. they i think must know, and history has proven that time and time again, that the united states and the uk are not really going to hold them responsible for this, and they're going to find a way out for them. that's happened before. in terms of the united states, president trump's, you know, reaction has veered between promising very severe consequences to saying that the explanations are credible, and talking about trade. right, i mean, and this is why very few people actually think that the united states is going to hold saudi arabia accountable for the murder of jamal khashoggi. i mean, it was like lie after lie after lie. and i think the onus of responsibility also lies with the turkish government,

that has been leaking information all week, with really truly gruesome details, and it's up to them as well now to release the facts — the video, the audio, whatever proof they have of how he was killed. i think at the least they owe it to the family ofjamal khashoggi, who i cannot even imagine what they've been going through for the past couple of weeks, with all of this information that's been leaking, and no—one is talking to them directly, and they don't know what's happened to him. i think it's cruel and unusual punishment, what they're doing to jamal‘s family. yeah, a personal tragedy wrapped up in international intrigue, it must be quite an ordeal for them. one of the bits of reaction from the 2a hours ago was senator lindsey graham, a republican who was very hostile to the explanation that came out of riyadh. do you think we are beginning to see the beginnings of a change in attitude towards washington—riyadh relations?

i hope so. i think it's the responsibility of congress, as well, to keep up the pressure, bipartisan pressure, on the white house, to force them to make an independent investigation into what happened. because i think it's — i think it's laughable that they're expecting that the saudi government is going to investigate itself and come with clarity and transparency, as they are claiming, forjamal, and that they're going to have anything independent that will hold the real culprits responsible for this. and so i think we all hope that congress will keep up the pressure on this because, i mean, lindsey graham, senator chris murphy — i mean, across the board they've been saying this. but how long will they say this when they think the story has cooled down? i mean, it's — time will tell. but even in the uk, with the yamamah deal,

for example, there were clear indicators, and very few people were held responsible for it. so sadly the west has had a very bad track record on holding the saudis responsible. yeah. there is another player in this, of course, and that is turkey. we keep on getting these leaks saying that there will be audio, there is audio. how much faith do you have that they are going to reveal the truth, after a thorough investigation? well, i think the fear is that there will be a deal between the saudis and the turks that will stop them from presenting the evidence, that they claimed for over a week now that they have, and so this is the true fear. is jamal‘s death going to be a political deal simply between the saudis and the turks? time will only tell, but i am not optimistic at all. donald trump says the us is planning to withdraw from a major nuclear agreement with russia dating back to the cold war. the treaty required both countries to get rid of short— and intermediate—range missiles, but washington has accused

the kremlin of breaching the agreement. here is our north america correspondent chris buckler. the intermediate—range nuclear forces treaty was seen as a landmark accord when it was agreed by russia and the us 30 years ago. it led to the destruction of hundreds of missiles by both countries, but the us has insisted that russia has abandoned the treaty by deploying banned cruise missiles. president trump now says that he is no longer prepared to let the kremlin violate an agreement that america has honoured. russia has violated the agreement. they've been violating it for many years, and i don't know why president obama didn't negotiate or pull out. and we're not going to let them violate a nuclear agreement and go out and do weapons, and we're not allowed to.

we're the ones that have stayed in the agreement, and we've honoured the agreement. but russia has not, unfortunately, honoured the agreement, so we're going to terminate the agreement, we're going to pull out. his national security adviser, john bolton, is holding meetings in moscow at the start of the week, and he is expected to tell russian leaders that the us is withdrawing from the treaty. let's get some of the day's other news: the brazilian authorities say the federal police will investigate huge amounts of fake news on social media regarding this month's presidential runoff election. it is alleged that supporters of the far—right presidential front—runner, jair bolsonaro, used whatsapp to spread disinformation targeting his left—wing opponent fernando haddad. mr bolsonaro's team has denied any wrongdoing. election results from iraqi kurdistan have confirmed the two main parties, the kdp and the puk, will continue to share power in the semi—autonomous region. opposition parties made little progress despite discontent over last year's failed bid for independence from iraq. the announcement was delayed

for three weeks while authorities investigated complaints of irregularities. a presidential candidate in georgia has been detained by police for handing out cannabis joints at a rally. zurab japaridze is running on a libertarian and pro—legalisation platform. he called his actions an act of civil disobedience and demanded the right to legally buy and grow marijuana in the southern caucasus nation. the election will be held on 28 october. hundreds of central american migrants have used rafts and boats to cross the river marking the border between guatemala and mexico in an attempt to continue theirjourney to the united states. thousands of people were left stranded on the frontier bridge after mexican police stopped them entering the country on friday. aleem maqbool reports. it is a bridge that

for the white house is now an immigration battlefield. straddling guatemala and mexico, it is currently home to thousands of migrants who have trekked from honduras, all wanting to get to the us. though they still have to get through mexico, which is not letting them in, president trump has described this convoy as an assault on the us, an onslaught of criminals. we plead to donald trump, this woman tells me. may god soften his heart so we can enter the us. children are sleeping on the floor, and we don't know how long we'll be here. it's not fair. it has been a heartbreaking time for some. we met linder, who got split up from his 13—year—old son five days ago, and hasn't seen him since. translation: i'm upset, and i don't know what to do. should i continue, and hope he arrives, or should i turn back? i need him so much.

they have all been risking the dangers, desperate for a better life in the states. well, small numbers of people have been allowed across the border, but for the most part the mexican gate has remained shut, and with living conditions here on the bridge getting more difficult, we are seeing many trying other means of trying to get the mexico. after a week of threats from washington, central american governments have come to an agreement to transport people back to their home country for free if they sign up. reluctantly, nearly 600 have already put their names forward. translation: we're sad because we thought we'd make it to the us. when you come from poverty, you try to be optimistic, but it's been difficult. we are returning to suffering. for some americans, the sight of migrants giving up is a welcome one.

for others, it is an embarrassment that their country, built on the idea of taking in those seeking prosperity, now delights in turning them away. but some migrants just won't take no for an answer. we saw some of the hundreds who had decided to cross into mexico by boat, determined and desperate enough to continue theirjourney to the usa by any means. stay with us on bbc news. still to come: peeling back to the futurist. the work of art hidden for 100 years is finally uncovered. a historic moment that many of his victims have waited for for decades. the former dictator in the dock, older, slimmer, and as he sat

down, obedient enough. dawn, and as the sun breaks through the piercing chill of night on the plain outside korem, it lights up a biblicalfamine, now, in the 20th century. the depressing conclusion — in argentina today, it is actually cheaper to paper your walls with money. we've had controversies in the past with great britain. but as good friends, we have always found a good and lasting solution. concorde bows out in style. after almost three decades in service, an aircraft that has enthralled its many admirers for so long taxis home one last time. this is bbc news. the latest headlines:

there has been international condemnation after saudi arabia admits the missing journalist jamal khashoggi was killed in its consulate in istanbul. president trump says the us plans to withdraw from a nuclear weapons agreement with russia, insisting moscow had violated the deal. it's now been confirmed at least 59 people died after being run down by a speeding train during a hindu festival on friday. it's india's worst rail disaster this year. eliza philippidis reports. dalbir singh will not be coming home to his wife again. he was just one of the thousands celebrating the ramlila festival, marking the triumph of good over evil. families and friends were out watching a burning effigy of the demon king as part of the festivities on friday when the train ploughed

straight through them. watching the fireworks from the train tracks, he, like so many others, did not hear the fast—approaching train. grieving relatives have been scouring the bloodied fields for anything their loved ones left behind. but anger is growing at the authorities over why the festival was allowed to be held so close to the train tracks. translation: when they have to get votes, they come along to beg from home to home. they did not come to see that our children have died. we should getjustice. local hospitals were overwhelmed with the number of people needing treatment. they quickly ran out of space for the dead and were forced to leave some bodies outside. police now say bodies were so badly dismembered that it will take days to identify many of the victims.

india's railway board has denied responsibility for the accident and the killing of those run down by the train. so far, the punjab chief minister has declined to comment on the likely reason behind the accident, but says he is committed to finding out what happened. we are announcing a magisterial inquiry, under our commissioner, who will hold a magisterial inquiry and give us a report within four weeks. the disaster near amritsar in the north of the country has led to new demands for safety reforms to india's accident—plagued railway system, which records thousands of deaths each year. the governments say they are keeping fares low for the 23 million passengers who use the network daily. but after decades of underinvestment, critics say this has left public safety at risk. several million afghans have voted

in parliamentary elections, the first to be organised entirely by the government since 2001. polling stations, which could not open on saturday, plan to do so on sunday. but the elections have been marred by violence as sekunder kermani reports from kabul. the taliban told them to stay at home. instead, afghans began queueing outside polling stations even before they had opened, with thousands of soldiers deployed across the country. 15 people were killed in a suicide bombing in kabul and there were dozens of other smaller incidents. but throughout the day, voting did go ahead. translation: of course everyone is scared, because security is bad. but despite all those fears, we are here and voting anyway, because our destiny depends on it.

translation: i hope the people who are elected will do something for the young generation and to improve security for the country. inside polling stations, women and men voted in separate sections. almost 9 million people have registered to vote for more than 2,500 candidates. despite the threat of violence, people here in kabul are turning out to vote, determined to have a say in how the country is run. but across afghanistan, nearly a third of all polling stations are closed because of security concerns. in a country where politicians are often seen as corrupt and linked to ethnic tensions, there's a degree of optimism about some of the candidates standing, many of whom are young and from professional backgrounds. the election process is the will of the people, and the people want to express their will by going to the polling stations, so that's why

the taliban were afraid. previous elections in afghanistan have been marred by allegations of fraud. many fear that will happen again despite new biometric devices meant to prevent anyone voting more than once. today's election is a key test of afghanistan's security forces ahead of next year's more politically significant presidential elections. it's been a day of defiance, but also, as it often is in afghanistan, of bloodshed. sekunder kermani, bbc news, kabul. a chinese—british team of cavers have found a giant cave hall in a sinkhole in southern china, which they think could be the world's biggest. the discovery was made in fengshan county in guangxi province. briony sowden reports. from above, it is an impressive

view. surrounded by steep cliffs, this 200 metre singh kohli and china's guangxi province is not an uncommon sight in the country's rugged landscape. but hidden beneath this one is what good be the world's tallest cave all, created because of colla pses tallest cave all, created because of collapses in the ground above. a tea m collapses in the ground above. a team of experts used just a single rope for the slow descent, more than 118 metres deep into the sinkhole. from the bottom, they used 3—d technology to scan the caves and underground holes where they discovered a giant cave hole and corridor. at a50 metres high, it is enough to fit the isil tower and a few olympic sized swimming pools. a courtyard itself is a grand 150 metres tall. but as well as being the world's is, it is also the thinnest with only a slim four

metres between the roof of the cave and the road above. the cave is in fengshan county, already popular with tourists because of its mountains, countless caves and underground tunnels, many of which have remained unknown until now. experts say this cave is mostly intact and sediments are well preserved and now hopeful that these discoveries will help them better understand how caves are formed in the area. a giant mural that's not been seen for nearly a century has been uncovered in rome. bal tic tac by the italian painter giacamo balla was found on the ground floor of a building owned by the bank of italy. the bbc‘s tim allman has more. art can appear in the most mundane of places. behind the walls of this fairly nondescript building, something from the past and the future. this mural, called bal tic tac,

a riot of red and blue and yellow was created to adorn the entrance of a popularjazz cafe in the 1920s. when the cafe closed, the mural was covered up and the building went on to become a lighting shop and then a bank. translation: i wouldn't hesitate to define this as an archaeological discovery of something modern. we knew it had been here, but we thought it was completely lost. on the contrary, it was still there, the freshness of the artist's work. that artist was giacomo balla. he was part of the futurist movement. his work embraced modernity and depicted light, movement and speed. translation: bal tic tac by giacomo balla was considered completely lost except for some pictures and sketches made by the artist. the survival of the mural under decades of paint and wallpaper

has been described as miraculous. it will now be restored and become part of a museum that should open at the end of 2021. then people will be able to see this artistic miracle for themselves. some pictures to bring you from sydney, australia now where the duke and duchess of sussex are spending the afternoon with the australian prime minister, scott morrison. harry and pregnant wife meghan had lunch with the pm and are also meeting members of the community and schoolchildren. it's part of their 16—day tour. a fireworks display in southern england is to be postponed because a beluga whale has taken up residence in the river thames. the whale, nicknamed benny, was first spotted in the river near gravesend, that's east of london, on 25 september.

the fireworks were due to be set off from a barge in the thames, but the local council says that benny's safety must take priority. in case you are feeling lucky and don't jacked to gambling, in case you are feeling lucky and don'tjacked to gambling, you will be pleased to hear this. —— don't object to gambling. a us lotteryjackpot has reached the record sum of $1.6 billion after months without a winner. the prize, known as mega millions, has been growing sincejuly. the next chance of drawing the six lucky numbers will be on tuesday. a reminder of our top story as with international condemnation after saudi arabia admitted the missing journalist jamaal khashoggi was killed in its consulate in east and all. -- in killed in its consulate in east and all. —— in east arnold. —— istanbul.

hello. for much of england and wales, saturday was a day of blue skies and sunshine. barely a cloud in the sky here in north yorkshire on saturday afternoon. as ever, there were some differences. western parts of scotland saw some mist, hill fog, patchy light rain and drizzle, and here's yet another contrast. with the help of the fern effect and some sunshine, aberdeenshire and moray saw temperatures around 20 celsius. now, through sunday, we've got a cold front slipping its way south and eastwards, some persistent rain across northern and western scotland, northern ireland through the morning. as it moves into northern england, the midlands and wales, the rain tends to fizzle out. so, we're just left with really a band of cloud and the odd spot of rain. some sunshine following on behind. a few showers for the far north of scotland, where it will be increasingly windy. ahead of our band of cloud, light winds, still some sunshine across southern and south—eastern england. and so here, we'll see temperatures up to 18 or 19 celsius, one last day of autumn warmth, and quite widely, 1a to 17 celsius on sunday. now, through sunday evening, here's our band of cloud continuing to weaken as itjourneys south and eastwards,

we'll see some clearer skies developing as we go into monday morning. more of a breeze, some drier air, so mist and fog shouldn't be too much of a problem first thing on monday morning. and we'll all notice a dip in the temperature, particularly across northern ireland, northern england and then scotland where temperatures will be getting closer to freezing. so, as we start the new working week, we've got this area of high pressure building, but notice this squeeze in the isobars. that's going to continue to bring some very strong winds to northern and western scotland, gusts of 50 to 60 miles an hour through the early hours of monday morning. further outbreaks of rain. but away from here, further south across scotland into northern ireland, much of england and wales, we're going to start the new week with plenty of sunshine. a cooler feel, though. we've got a brisker northerly wind. so, compared to the highs of 19 or 20 celsius, it's going to be more like 12 to 1a celsius on monday afternoon. it's a similar sort of day on tuesday. we've still got this area of high pressure, it's a really dominant feature through much of next week. still some windy conditions to the far north of scotland

and some outbreaks of rain, and it looks like some of that rain could just filter a little bit further southwards down towards the central belt, maybe towards the borders on tuesday. more cloud around for northern ireland and the far north of england. but elsewhere, further south across england and wales, once again, there'll be a good deal of sunshine, but a brisker north or north—westerly wind with temperatures again just 12 to 1a celsius. so, to sum up the week ahead, away from the far north of scotland, it's looking mainly dry, there'll be some sunshine, but it is likely to turn colder by next weekend. bye— bye. this is bbc news. the headlines: turkey has promised to reveal every detail about the killing of the journalist jamal khashoggi, who died inside the saudi consulate in istanbul. there has been international condemnation after riyadh said mr khashoggi died as a result of a fist fight. donald trump says the us is planning to withdraw from a nuclear weapons agreement with russia. the treaty required both countries to get rid of short— and intermediate—range missiles,

but washington has accused the kremlin of breaching the agreement.