welcome to bbc news, broadcasting to viewers in north america and around the globe. i'm reged ahmad. our top stories: hours before voting is due to begin, nigeria's presidential election is postoned. we'll be live with the very latest. donald trump invokes national emergency powers to fund the border wall with mexico. his opponents are furious. we are going to confront the national security crisis on our southern border, and we are going to do it, one way or the other we have to do it. the family of the pregnant teenager who joined the islamic state group pleads with the british authorities to help bring her home. and junk in space. engineers test a new satellite harpoon system for collecting floating trash. we begin with breaking news from nigeria.

the electoral commission has postponed the presidential election by a week, just a few hours before voting was due to begin. the commission chairman yakub mahmood said that it was not logistically feasible to proceed as scheduled. he called it a difficult decision, but necessary to ensure a free and fair vote. let's get the latest now from our correspondent in yola, in the north—east of nigeria, mayenijones. how unprecedented is this move? u nfortu nately not unfortunately not unprecedented. last two elections, in 2015 and before that in 2011, were also postponed, although the 2015 once came with some more warning. the

once in 2011—— came with some more warning. the once in 2011 —— ones came with some more warning. the once in 2011—— ones in 2011, at least the national assembly elections, were postponed on the day as well. so this is unfortunately something nigerians are used to. following the 2015 elections, which we re following the 2015 elections, which were considered to be quite successful, things went fairly smoothly, people thought we had entered a new era of nigerian politics, where perhaps things would be more organised. this will be a disappointment to many people in nigeria who will wake up in the morning to this news, particularly those who have had to travel long distances to vote, because not everybody votes where they live. some people might register to vote in their home towns, and they have travelled several hours to get there, and then they will find it was to nothing. it is obviously the middle of the 19 nigeria, but presumably there has been reaction into this news? —— middle of the night in nigeria. yes, the ruling party, the all progressives congress, has already released a statement. they condemned the

postponement of the elections. they say that they had absolutely nothing to do with it, that as a matter of fa ct to do with it, that as a matter of fact this works against them because they believe they would have won the elections have they happened today. they urged all of their supporters to remain patient and to stay calm. now, is there any sense of what the reaction might be, if people are being urged to stay calm, do you think that there could protests?m the past there has been a lot of violence around nigerian elections, peptic yulia after postponements have happened or when results were announced, with the losing side sometimes retaliating. it is unclear as of yet how things will turn out. yola is in the home state of the main opposition candidate, atiku abubakar, who is yet to comment on this postponement. we will be watching closely to see what he says, whether he urges his supporters to stay calm, and what

happens suddenly. it is very tense. the atmosphere prior to the elections was very tense, there was an escalation of rhetoric from both sides, as we got to the end of campaigning. so everybody will be watching anxiously, particularly in the wider region. nigeria is a phenomenalforce in the the wider region. nigeria is a phenomenal force in the wider region, it is the biggest economy in africa, it is the constant‘s most p0p africa, it is the constant‘s most pop illustration. it is incredibly influential. —— most populous nation. its stability affect the stability of the rest of the continent. the commission chairman gave us continent. the commission chairman gave us some continent. the commission chairman gave us some sense continent. the commission chairman gave us some sense of continent. the commission chairman gave us some sense of perhaps the reasons for this postponement, but do we have any further insight as to why this kind of action was taken literally hours before polls were due to open? yes, unfortunately he did not give many details. there had in rumours swirling around throughout the day, but when he eventually did come and address the public, all he said was that there we re public, all he said was that there were logistical issues. in the weeks running up to election day, there

had been fires at a number of polling stations in different parts of the country, including central nigeria but also in the south—east. at the time, the electoral commission said they were perfectly equipped to deal with those incidents, that they have replacement voting booths and replacement voting booths and replacement voting booths and replacement voting cards which have been burnt at the time. it seems that. reason, perhaps because of those fires or other logistical reasons, they were not able to deliver the promised to have the vote ta ke deliver the promised to have the vote take place today. and just briefly, can you tell us a little bit more about the actual election race, whether the incumbents, muhammadu buhari, was set to win, or whether it might go to the opposition? it was expect it to be a very tight race. both president muhammadu buhari and the main opposition leader, atiku abubakar, have been in politics for a very long time. between them they have tried to be president nine times. they are both from the north of the

country, so they are believed to have a similar support base. many a nalysts have a similar support base. many analysts here thought it would eat too close to call. with all of the latest on that breaking news, nigeria's electoral commission postponing the presidential election, of course, we will keep you up—to—date with that story as it continues to progress. after weeks of speculation, president trump has defied his critics, and many in his own party, by declaring a national emergency. it means he can now bypass congress, to get the billions of dollars he says he needs to build a border wall with mexico. those funds will come from other government departments. but democrats have launched an investigation saying the move is unconstitutional and they'll fight him all the way to the supreme court. 0ur north america editor, jon sopel, has more from washington. ladies and gentlemen, the president of the united states. donald trump had an unpalatable choice. having not got a deal with congress, he was either going to have to admit failure on funding his wall with mexico, his signature campaign pledge, or he was going

to have to go nuclear. he chose nuclear. this was now a national emergency on the southern border. we're going to be signing, today, and registering, national emergency. and — it's a great thing to do, because we have an invasion of drugs, invasion of gangs, invasion people, and it's unacceptable. watched by relatives who have had family members killed by illegal immigrants, the president rode roughshod over the powers of lawmakers to set budgets and to set up a confrontation with congress that he fully recognises is likely to end up in the courts. we will have a national emergency and we will then be sued and they will sue us in the ninth circuit, even though it shouldn't be there. and we will possibly get a bad ruling and then we will get another bad ruling, and then we ‘ll end up in the supreme court.

and all the time the courts are deliberating it means there will be no substantial building work taking place. less building a wall than hitting one. but here's the problem. there's a lot of of fencing and structures — but there are places where itjust ends, so people like his mother and child from guatemala just can walk round it. "my little girl is hungry," she says, "and i don't have any money." in recent years, the number of illegal immigrants trying to enter the us has been in decline. and most of the drugs that enter the country from mexico come from legal crossing points — like this one. but a lot of border patrol officers who backed the president's call for a wall make this point about the problem subsiding. i would say it's nothing like it was. i would say that it's changed. but that is the equivalent of saying your house is only getting robbed one day out of the week now, instead of all seven, then you're done. we're not done. back in washington, the democrats are considering their next move. it's hard to believe

they won't challenge this. president trump couldn't convince mexico, he couldn't convince the american people, he couldn't their elected representatives to pay for his ineffective and expensive wall. make no mistake, congress will defend our constitutional authorities in every way that we can. donald trump's signature is now on this declaration. there are many on both sides of the divide who question how much of a national emergency this really is. and it won't be lost on them that on day one of the emergency the president flew off to his golf course in florida, not the border with mexico. jon sopel, bbc news, in washington. let's get some of the day's other news. five people have been killed in a shooting at a warehouse near chicago. police said the gunman was shot dead by their officers. it happened in an industrial area

on the outskirts of aurora. at least five police officers are amongst the injured. the turkish president, recep tayyip erdogan, says his country is determined to take the investigation into the killing of the saudi journalist jamal khashoggi to an international court. mr erdogan said turkey had not so far disclosed all the documents and information it had concerning the killing, but would deliver them to investigators. the body of the argentinian football player, emiliano sala, has arrived back in his home country ahead of his funeral on saturday. the 28—year—old died after the plane he was flying in crashed into the sea between france and britain as he was travelling to his new club, cardiff city. relatives of a teenager from london who went to join so—called islamic state have asked the british government to help them bring her home. the family of shamima begum, who was 15 years old when she left

the uk, said they understood she would be investigated and they welcomed that. there's also a new warning from the head of britain's intelligence agency, m16, that thejihadists still pose a threat. daniel sandford has more. inside the al—hol camp in northern syria, the women and children fleeing the fighting in one of the last strongholds of the islamic state group. this is where the former bethnal green schoolgirl shamima begum is. her family had lost all hope of seeing her again. and tonight, in a statement, they asked the british government to help them to return her, along with her unborn baby. "as a british citizen," they said, "shamima has every expectation to be returned to the uk and be dealt with under the british justice system." "shamima's child, who will also be british, has every right, as a total innocent, to have the chance to grow up in the peace and security of this home." they said they would welcome the police investigating her, something that is inevitable if she returns. we have to be clear that people who leave this country to support that regime are people who, if they do return, have to answer for their actions. some 850 people left the uk to join

is and around half have already come back. today alex younger, the head of the secret intelligence service, mi6, warned that at least some returnees will pose a risk. "experience tells us that once someone puts themselves in that sort of position they are likely to have acquired the skills and connections that make them potentially ver the home secretary said this morning that he would prevent those involved in terrorist organisations returning to britain. but what does that mean for shamima begum, who left the uk as a schoolgirl? could she have her citizenship taken away? if she doesn't have another nationality, as i believe to be the case, then it is morally unacceptable to refuse her entry — as well as legally unacceptable. because otherwise she would be stateless. and no person in the world can be stateless under the law. her family said they were shocked to hear her say she didn't regret

going to is. they explain it by suggesting that she was groomed at the age of 15 and might have been wary of what she was saying in a camp surrounded by is sympathisers. and rashad ali, who is an expert in de—radicalisation, says is supporters can be turned round. we know in the uk we have worked over the last ten years with fairly hard—line violent extremists who have renounced their ideology, have remorse for their actions, and have taken part, actually, in helping others move away from extremist tendencies and violent ideologies. the kurdish red crescent says there are around 1000 new arrivals at al—holjust this morning. decisions will have to be made soon about what to do with the british is supporters among them. daniel sandford, bbc news. stay with us on bbc news,

still to come: hot on the trail of the million—dollar rhino horn smugglers — the latest arrests come weeks after the seizure of eight tons of pangolin scales, and more than 1000 elephant tusks. nine years and 15,000 deaths after going into afghanistan, the last soviet troops were finally coming home. the withdrawal completed in good order, but the army defeated in the task it had been sent to perform. malcolm has been murdered. it has a terrible effect on the morale of the people, i'm terrified of the repercussions in the streets. one wonders who is next. as the airlift got under way,

there was no letup in the eruption itself. lava streams from a vent low in the crater flowed down to the sea on the east of the island, away from the town for the time being, but it could start flowing again at any time. the russians heralded their new generation space station with a spectacular night launch. they've called it mir, the russian for peace. this is bbc news, the latest headlines: hours before voting was due to begin, nigeria's electoral commission blames "logistical reasons" for postponing the presidential election by a week. donald trump invokes national emergency powers to fund the border wall with mexico. the democrats accuse him of an abuse of power. two men have been arrested by airport authorities in hong kong, for allegedly smuggling a record number of rhino horns worth $1 million.

the men were on their way to vietnam from south africa. it comes just two weeks after a seizure of eight tons of pangolin scales and more than a thousand elephant tusks. we're joined on the line byjohn baker, who is the chief programme officer for wildaid. thank you for your time are you surprised by this record all that they have found ? surprised by this record all that they have found? -- record haul. rhino horn smuggling, yes, that is quite surprising. there are more and more people getting arrested trafficking on airlines, and this seemed to be quite a risky move on the part of these two gentlemen. seemed to be quite a risky move on the part of these two gentlemenm it is surprising, what does it tell

us it is surprising, what does it tell us about the trade with rhino horns? betrayed is active and ongoing, and the thing that we are surprised that in this case is how many horns these two individuals were carrying. normally we would see people carrying maybe three or four horns ina carry carrying maybe three or four horns in a carry on, most rhino horn is carried on airlines by passengers. this is off the back of another seizure in hong kong, pangolin scales and elephant tusks, is hong kong quite a hotspot for things like this? yes, hong kong is it midst of —— in the midst of the higher centre of demand, whether it is rhino horn 01’ of demand, whether it is rhino horn or pangolin or ivory. from hong kong it can go to mainland china, it can go to vietnam, which is... some

people in hong kong who buy these products. i'm so sorry, john, the quality of the lion has really deteriorated, we would love to have spoken to you a lot longer. —— quality of the line. schoolchildren across the uk, have been taking part in a day of protests, calling for action on climate change. 0rganisers say pupils walked out of schools in more than 60 towns and cities, to highlight what they see as a lack of action by the government. frankie mccamley reports. we are angry that the government's not doing anything, but we also see it as important to fight for ourfutures. to all the politicians, listen to what we have to say. you failed at saving your own future, so now can you try and save ours? there's no time to rest. we have to do something to save the planet. chanting: this is what democracy looks like!

different voices, one clear message. today was a day led by the children, for the children and their future. thousands campaigned in dozens of protests across the country. they say you don't have a voice! a call for action in sheffield... what do we want? climate action! chanting in ullapool. .. marching in brighton... a real sense of urgency in cardiff and, in manchester, there was music. # born to love in everyone... before nine—year—old lilia had her say. i'm worried about climate change because of the animals. would you like it if your home was disappearing in front of your eyes? this is clearly the first time many of these pupils have ever walked out of school and, just by looking at the age of some of these, the first time they've ever been on a protest, but their message is clear. they want to protect the future of the planet and safeguard their future. the action is part of a much

wider global movement, inspired by 16—year—old greta thunberg from sweden. she's been striking from school every friday, calling on her government to lower its carbon footprint. you are not mature enough to tell it like it is. even that burden you leave to us children. her persistence later sparked protests across the world — from australia to belgium and ireland earlier this week. the government has said today's protests are a waste of lesson time and increasing teachers' workload, but the threat of school disciplinary action pales in significance to the danger these youngsters think the planet is under from climate change. engineers say they've successfully found a new way to tackle the build—up of space debris. a team from the uk have used a harpoon—capture system on board a satellite to collect orbitaljunk.

0ur science correspondent, rebecca morelle reports. this is the moment a harpoon was fired in space. striking a target almost dead centre, it was filmed 250 miles above the earth. it's the latest experiment from the remove debris spacecraft. led by surrey university, it's a mission that is testing out the technologies that could clean up space junk. it was absolutely a success and the goal of the experiment was to hit the target and that's what we did. it's important because there's so much debris up in space, from spacecraft that are no longer operational to bits of rocket body, and we need to start clearing some of this debris out of the way to make way for new spacecraft. space is becoming increasingly cluttered. it is estimated there are now nearly 8,000 tons of debris, with 800,000 pieces the size of a marble or bigger, and each piece has the potential to do some serious damage. in 2016, this crack in the window of the international space station

was thought to have been caused when a tiny fleck of paint hit it. bigger objects could do even more harmful. bigger objects could do even more harm. scientists are particularly worried about a european satellite the size of a double—decker bus that stopped working in 2012. it's now threatening other satellites in its path and needs to be remove from its orbit. last year, the remove debris spacecraft also tested a net, proving it could catch a passing satellite. it's the first mission to try and address this problem. and it's also used its onboard cameras to track a tumbling target. essential for hunting down any rogue space litter. its final test will be in the coming weeks. it's set to burn up as it returns to earth, preventing it from becoming a piece of space junk itself. the hope is now that future missions can be scaled up so the celestial deep clean can begin.

the award winning british author andrea levy has died. she was 62 and had been receiving treatment for breast cancer. the daughter of windrush generation parents who came to britain from jamaica in the late 1940s, her books chronicled the highs and lows of the black british experience, most notably in her celebrated work, small island. lizo mzimba looks back at her life. archive: the empire windrush brings to britain 500 jamaicans. .. in 19118, andrea levy's father arrived on the empire windrush. it was the inspiration for her novel which charting the hopes and struggles of a generation, small island. it went on to win multiple awards and be adapted for tv and the stage. when it first came out, you know, i sort of said to the publicist, "just give me a basket, i'll take it door—to—door". i really thought nobody was going to be interested. you think your white skin make you better

than me, don't you? we both finished fighting a war for a better world. we was on the same side. if anybody wants to have a look at how the windrush generation arrived here, and how we, the sons and daughters of the windrush generation, survived and are surviving, they have to refer to andrea's work. that's why, for my generation of black people in this country, there's always a andrea levy book on our bookshelves. andrea levy had grown up in london, and in her 30s had begun to write. her work was driven by her own curiosity about where she'd come from. it was a story that eventually took her back to britain's role in the caribbean slave trade. for every one slave who went to america, 12 went to the caribbean. it was massive — it was massive.

i have seen books on british history that don't mention slavery, you know, and you just sort of... it beggars belief. the character she created was a house slave who bore a child to an estate master and then later, she discovered that that was the story of her own great—great—grandmother. andrea levy, an author whose life and work was rooted in the story across generations of two small islands, britain and jamaica. andrea levy, who's died at the age of 62. let's remind you of our breaking story, nigeria's electoral commission has postponed the presidential election by a week, just hours before voting was due to begin. stay with us on bbc news. hello.

judging by the weather over the past few days it looks like spring is in a hurry to start. and, well, apart from the cloud that moved into northern ireland and western scotland, friday brought plenty of sunshine again and the warm spot was in wales. this view from wrexham. it was in rhyll, actually, in north wales, where the temperature reached 17.5 degrees celsius. that's even higher than thursday's top temperature. and over the weekend we are we are still in this lower, mild air heading in from the south. though there are a few weather systems coming our way. so we can't rely on clear blue skies. here's the first week one that's moving across northern scotland, with some outbreaks of rain. another one will come in during sunday. so, for the weekend then, it is still mild. temperatures are above average for the time of year. it will be breezy, especially on sunday. it will be dry for many. though these weather systems will bring a bit of rain, especially to western parts of the uk. and, already, as saturday begins, things are different. not as cold as recent mornings. more cloud around as well. still the leftovers of some overnight rain affecting parts of western and northern scotland before that eases. we're going to keep a lot of the cloud feeding into southern

england. that's going to edge further north. elsewhere it's sunny spells, rather than clear blue skies on another breezy day. so a closer look at things at four o'clock in the afternoon. should start to see some sunshine coming back into the channel islands. could be some coast and hill fog from the thicker clouds in the south, maybe the odd bit of drizzle. cloud increasing for wales, the midlands, into east anglia. but still sunny spells in northern england and a few breaks in the cloud for northern ireland and scotland. best of the sunshine here will be in the east. but cloud thickening in the western isles, again, the northern isles still seeing a bit of patchy rain. could see the odd shower pushing in towards cumbria, lancashire, too. but most places are looking dry. 0vernight we are going to get rid of quite a bit of the cloud, so clearing skies for many of us. though temperatures aren't going down too far into sunday morning. so no issues with frost. then the next weather system i pointed out is starting to bring its wet weather into the west. it's going to weaken as it slides further east during the day. so we're not going to see too much in the way of wet weather

out of this. it is a windier day with this weather system, though, approaching and moving through during sunday. but there is more sunshine around ahead of this system. and it's a fairly narrow one as well. just cloud, a bit of patchy rain working through. clearing through northern ireland. any heavier bursts of the rain, really, into northern parts of scotland for a time. quite windy in western scotland. some gusts up to 50 mph or so. and notice temperatures are just on the up a little bit more compared to saturday. especially, of course, where you get to see some sunshine. eastern part of the uk look mainly dry. not as mild into the start of next week. and still a fair amount of cloud around. this is bbc news, the headlines: nigeria's electoral commission has postponed the presidential poll by a week — hours before voting was due to begin. the commission chairman, ya kub mahmood says it wasn't feasible to proceed as scheduled for logistical reasons but the delay was necessary to ensure a free and fair vote. the us president donald trump has declared a national emergency

in an attempt to bypass congress and secure funding for his mexican border wall. democrat leaders have described it as "a gross abuse of power" and announced an immediate investigation into the declaration, which they say violates the constitution. relatives of shamima begum, the pregnant teenagerfrom london who went to syria to join the islamic state group, have asked the government to help them bring her home. britain's home secretary, sajid javid, has made it clear he'll try to prevent the return of people who've supported terrorist organisations.