it is like a soldier on a battlefield, you don't know what you will be faced with. on top of that, you have got the fear, am i going to make it home tonight? the brexit bill is published, causing tension within labour, which tells its mps — you must vote for it. and one of the leading contemporary art prizes in the world — won tonight by a british artist and film—maker. and coming up in sportsday on bbc news: manchester united went behind in their efl cup semifinal second leg at hull. find out if they could hold onto their aggregate lead to reach the final at wembley. good evening. theresa may has arrived in america at the start of a trip which she hopes will pave the way for a post—brexit trade deal with the united states. she'll be the first foreign leader to hold talks with donald trump, when she meets the new president at the white house tomorrow. this evening, she addressed a republican conference in philadelphia, in a speech where she sought to find common ground with mr trump. but the prime minister's bid to launch a new era of co—operation with america risked being overshadowed — by a row about president trump's support for torture, and in particular, water—boarding. our political editor laura kuenssberg is travelling with theresa may and has just sent this report. opposites attract. theresa may's hope. but how close does she want to get to him? the prime minister made a quieter arrival, making her way down the windy steps in philadelphia. her convoy speeding towards her debut in trump land, here to make friends. no hate, no fear. a reminder right outside the 5—star hotel where they were both to speak, donald trump has many enemies as well. the prime minister's warm up as well. the prime minister's warm up tax was the president himself. is he ready for her? i'm meeting with the prime minister tomorrow, as you know. great britain. i'm meeting with her tomorrow. i don't have my secretary, they want to talk trade, so secretary, they want to talk trade, so i'll have to handle it myself. laughter which is ok. then it was her turn, with, as you would expect, fulsome reference to the french —— friendship across the atlantic. reference to the french —— friendship across the atlanticm has been america's destiny to bear the leadership of the free world and to carry that heavy responsibility on its shoulders, but my country, the united kingdom of great britain and northern ireland, has been proud to share that burden and to walk alongside you at every stage. applause cheering but this is much more than a meet and greet. theresa may came with a serious message for republicans and the world cup. under her leadership, no more western conflicts like iraq, or afghanistan, she suggested. this cannot mean a return to the failed policies of the past. the days of britain and america intervening in sovereign countries in an attempt to remake the world in our own image are over, but nor can we afford to stand idly by, when the threat is real and when it is in our own interests to intervene. we must be strong, smart and hard—headed, and we must demonstrate the resolve necessary to stand up for our interests. and a warning perhaps directed at the president over an assertive russia. when it comes to russia, as so often it is wise to turn to the example of president reagan, who, during his negotiations with his opposite number mikhail gorbachev, used to abide by the adage, trust, but verify. with... applause with president putin, my advice is to engage, but beware. noticeable as well, her praise for the republicans, and president trump's controversial win. because of what you have done together, because of that great victory you have won, america can be stronger, greater and more confident in the years ahead. even before she touched down though, theresa may had a taste of how much political trouble closeness to president trump could cause. number ten believes the risk is worth it, because there's a big opportunity as well, but this new friendship could cause fireworks. every time donald trump's speaks his mind. suggesting torture, banned under british and international law, works. torture, banned under british and international law, worksi torture, banned under british and international law, works. i want to do everything within the bounds of what you're allowed to do legally, but do i feel it works? absolutely i feel it works. prime minister was adamant britain won't change its laws and signalled we might stop sharing intelligence with america if torture was brought back. here among the republican top brass, the unlikely —— the idea is unlikely to fly. the deep-seated policy in american culture is not to torture. so theresa may is right and president trump is wrong?” so theresa may is right and president trump is wrong? i didn't say that. just one of many awkward subjects the pm and president could discuss tomorrow, a test, even in politics true friends tell the truth to one another, not merely platitudes, or what they want to hear. laura in philadelphia, theresa may clearly trying to set the tone of the relationship she would like the uk to have with donald trump. that's right, in the city where american revolutionaries at the time through off their attachment to the uk and declared independence, theresa may came here with much more than brought warm words about the importance of our traditions and shared history. she came signalling for example a clean break with failed, as she suggested, foreign policy of the past, interventions that america and britain had been involved in clearly signalling what had happened in iraq and perhaps afghanistan, where american presidents had taken british prime ministers into conflicts that had worked out badly, very interesting that she used this big, major appearance here to signal such as shift. but more broadly, how does the self—described hard—working vicar‘s door to reconcile herself to work with the reality tv star billionaire president? the answer from this speech was, with great ca re from this speech was, with great care and calibration. there were su btle care and calibration. there were subtle criticisms, warnings for example one russia, but for example on nato, where president trump has expressed doubts, she said she shared some of those doubts but insisted britain and america must continue to work hard, to make sure that nato still really matters. as ever with theresa may, no single word was wasted. everything was in there, carefully put there, with meaning behind it. but tomorrow, she is off to the white house and the talks will turn to trade. the audience here, republican in philadelphia, is needed —— is the audience to be friends with president trump than it is back home in downing street is well aware this relationship is extremely important, but they also know how controversial it could be. it's not so much that she's trying to walk a fine line, it's more like she's having to tiptoe across a tight rope across the whole of the grand canyon. laura in philadelphia, thank you. our diplomatic correspondent james robbins is with me. you were listening to mrs may's speech in philadelphia. one thing that stood out was what she appears to be signalling, a change in uk foreign policy. this is a hugely significant speech. arguably the biggest by a british prime minister in the united states since tony blair's in chicago in1999, states since tony blair's in chicago in 1999, when he first, openly advocated armed intervention is against dictators, and of course that was repudiated by theresa may this evening. as if to underscore the failure of current british policy, the foreign secretary boris johnson earlier on today told a committee of the house of lords that, now the policy in britain had changed, and that president assad should be permitted to run for election, as part of a democratic resolution of the syrian civil war. that's a complete reversal of british foreign policy. boris johnson himself called it, a com plete johnson himself called it, a complete flip—flop, but he said, the uk had been unable at any stage to fulfil its mantra that the syrian president should go. now, by boris johnson saying it, it meant theresa may didn't have to, but those are pretty painful words to have to utter. there is more in the prime minister's speech that we've been listening to. she is challenging donald trump, particularly over nato and the un, and the —— i think she's signalling it will be a bumpy special relationship. meanwhile, president trump had other things in his mind than his meeting with mrs may. relations between the us and mexico have soured still further. following a tweet from mr trump suggesting their meeting next week should be scrapped, the mexican president retaliated by cancelling it. the row centres on president trump's plans to build a wall along the mexican border, and his repeated insistence that mexico will pay for it. our north america correspondent nick bryant reports. donald trump's new executive toy. its first ride today on air force one, that potent symbol of us presidential power. but it was the cancelled travel plans of the mexican president that were wrapped the centre of a diplomatic storm. his plane will stay grounded after a summit between the two leaders scheduled for washington next week was abruptly called off. this mexican stand—off is over the great totem of the trump presidency, the wall he is determined notjust to build along the border, but also to get mexico to pay for. but in an angry speech last night, the country's president, enrique pena nieto, said he wouldn't foot the bill. so shortly before leaving the oval office this morning, donald trump decided to conduct his diplomacy by tweet. if mexico is unwilling to pay for the badly needed wall, then it would be better to cancel the upcoming meeting. by the time he spoke in philadelphia, the time he spoke in philadelphia, the mexicans had announced the summit was off, and that earned a public scolding from president trump. the president of mexico and myself have agreed to cancel our planned meeting scheduled for next week, unless mexico is going to treat the united states fairly, with respect, such a meeting would be fruitless and i want to go a different route. almost a week into his term in office it's already becoming clear that donald trump is changing the presidency more than the presidency is changing him. on prime—time tv last night, the former property tycoon gave a tour of the country's most prized piece of real estate and it was vintage donald trump. i don't want to change too much. i can be the most presidential ever, other than possibly the great abraham lincoln, all right? buti can be the most presidential person. he's still obsessed with the crowd size that his inauguration. but in a new interview with fox news, he turned his attention to the group calling itself islamic state, saying its fighters were thick and demented. the people we are going against, they don't wear uniforms, they are sneaky, dirty rats. and they are sneaky, dirty rats. and they blow people up in a shopping centre. and they blow people up in a church. these are bad people. the presidency is travelling at a hurtling pace. the late—breaking news tonight, that is now calling for a 20% tax on mexican imports to pay for the wall. donald trump is clearly revelli ng in pay for the wall. donald trump is clearly revelling in his seat of power, whether it's in the oval office, or at 30,000 feet. beautiful, great plane. nick bryant, bbc news, washington. let's talk to our north american auditorjon sopel our north american auditorjon sopel, at the white house. it's difficult to keep up with events. there's the tax with mexico, executive orders, he's picking fights with mexico. there are the announcements that they have anticipated and planned for, and there's what they call in the white house, stray voltage, where things haven't gone quite exactly to plan, and there's been a lot of that today. you've had the top team at the state department, civil servants resigning en masse, you've had all manner of other things as well, the row over torture with the republican leadership distancing themselves from him, you've had the concern over him signing an executive order looking into electoral fraud, over him signing an executive order looking into electoralfraud, even though the evidence is very scant on that, and indeed, so much so that a p pa re ntly that, and indeed, so much so that apparently one of the reasons donald trump believes that, he was told it was so by the german golfer bernhard langer. these are some of the things that are moving donald trump in a certain direction. on top of that we've had the mexican president announcing that he's not going to come to washington after all. there seem to be limits on twitter diplomacy. let's talk about the meeting with theresa may tomorrow. what reception is she likely to get there? i think she's going to get a very warm reception. i thought what was notable about her speech was how loudly she proclaimed her closeness and was very subtle about the differences, as laura was saying, that she has with this administration. but this is all about trade, and getting a deal, if and when britain leads the single market, which seems to becoming more and more certain. the thing you have to ask is, who needs that trade deal more? donald trump, ortheresa to ask is, who needs that trade deal more? donald trump, or theresa may? theresa may is clearly the answer to that question, which means she's going to have to tread very carefully with donald trump, who may be offering her all sorts of nice things, but there may be trapped in there as well. jon sopel at the white house, thank you. here in the uk, strong consumer spending helped the economy grow faster than expected at the end of last year. figures show it grew by 0.6% in the october to december period. it means the british economy expanded by two per cent last year, confounding predictions from some economists that there would be an immediate slowdown after the brexit vote. the chancellor philip hammond said the figures show the economy is robust, but warned there could be a period of uncertainty ahead, as our economics editor kamal ahmed reports. it was napoleon who famously and sarcastically called us a nation of shopkeepers, and the government will be pleased today the uk economy is still one based on consumers and the high street. britain's services sector, 80% of the economy, was the reason for the positive growth figures. for shoppers in reading, it was good business as usual. a lot of people thought that the referendum and the vote to leave the eu would mean consumers might be nervous, "what does the future hold? and would stop spending. did you find that was true? no, i haven't seen any difference personally. i think consumer spending will maintain itself and, long—term, i think we are in for a good ride. i think we are in a terribly unstable situation, i really do. we have got nothing that is filling us with confidence. instability, lack of confidence. they drove a myriad of warnings before the referendum. there would be a hit to the value of people's homes, at least 10%, and up to 18%. material slowdown in growth, notable increase in inflation. higher prices, less growth means less jobs, so higher unemployment. we are indeed a nation of shoppers and, frankly, those gloomy predictions before the referendum haven't come to pass. consumer confidence is still strong, business confidence is still strong, but with inflation rising and britain actually still to start the process of leaving the eu, which of course we haven't done yet, will that confidence remain? the chancellor meeting apprentices at microsoft, near reading, a company that is investing in the uk. i met him later and asked him about the bank of england forecast which said growth could slow next year. is this economic pain cancelled or is it delayed? what the figures today show is that the uk economy continues to be resilient and continues to confound the sceptics. of course, we recognise that as we go into this period of negotiation with the eu, and as we absorb the impact of the depreciation of sterling last year, there will be more uncertainty ahead during the course of this year. british—built cars off to the continent today, a mark of optimism, as production reached a 17—year high and exports hit a record. there is still, though, the brexit shadow. we are getting comments from a number of our members saying they are sitting on their hands, waiting to see what the future will hold, and looking for greater certainty about future relationships, especially with europe. the nation of shoppers forges on. britain's growth last year was the highest of any of the major western economies. are we still waiting for the full brexit effect? the labour leaderjeremy corbyn says his mps will face a three—line whip compelling them to vote to trigger article 50, allowing the start of brexit negotiations. that's prompted one shadow minister to quit the front bench in protest. a two—line bill on the issue entered the commons today, with a vote expected next week. our deputy political editorjohn pienaar is at westminster for us tonight. john, first of all, what's in the bill, and will it get through parliament? yes, theresa may hoped to get brexit started without getting an ok from parliament, the supreme court said we need this. you could write it on the back of an envelope and have room to spare, it gives her authority to get the negotiations to leave going, and take it from there. it will pass comfortably, by the look of things, because most mps have decided they cannot defy the referendum, and jeremy corbyn has told his mps they can try to influence the outcome, but they cannot stop brexit. how cookie is it forjeremy corbyn? it is difficult forjeremy corbyn? it is difficult for labour. the tories were always the party with a running schism over europe, and now it is labour's term, because their mps come from areas that voted to leave. he has persuaded some of these unhappy ministers to go along with this, but one of them has resigned. others will vote against it. he will have to decide whether to sack them. it leaves labour split on tactics and policy, and ministers confident of getting at least to the starting line of this marathon over an obstacle course towards brexit. there's been a record rise in suicides, assaults and self—harm inside prisons in england and wales, and the latest figures are a stark reminder of the crisis in the penal system. there were 354 deaths in prison custody last year. more than 100 were suicides. nearly 6,500 staff were assaulted in the year to last september. that's a 40% increase. and incidents of self—harm are up by nearly a quarter. our home affairs correspondentjune kelly has been speaking to one prison officer about life inside the prison walls. life in ourjails is getting worse, for staff and prisoners. the rise in assaults, suicides and self—harming is relentless. the sense of crisis in the system was underlined by a riot in birmingham prison, where inmates posed in helmets stolen from staff. just one of a string ofjail disturbances in recent months. amid the volatile atmosphere, today's figures show that in the past year a record number of prisoners have taken their own lives. it's very hard when you've got members of your family who... sarah is a long—serving prison officer, whose identity we are protecting. she describes having to deal with a teenage suicide. a self—inflicted death is an horrific experience. you feel, is there something more i could have done? he was only 19. i came on duty, and i went to perform a roll check. i lifted the flap, and this young man was suspended in his cell. he'd hung himself overnight. we lay him on the bed, and i saw a note to his sister on the side, and i saw it was his birthday, and i thought, what a waste. that will stay with me. just describe the thoughts in your head as you're going into work. i go into work feeling anxious. tensions are high. prisoners are angry and frustrated. when you open a door, you don't know what you're going to be faced with. i've had everything from urine, faeces, televisions thrown at me. spice in a jar. prisons are awash with drugs and psychoactive substances which are meant to be banned. all adding to the underlying problems of staff shortages and overcrowding. vulnerable prisoners are suffering in the increasingly—threatening environment in some jails. i'm very clear that the levels of violence in our prisons are too high, and the levels of self harm are too high. since i becamejustice secretary, i've focused on dealing with this problem. that's why we're investing an extra £100 million. 2,500 extra prison officers across the estate, so that we are able to have a caseload of one prison officer for every six prisoners. but sarah says the challenge is not recruiting staff, it's retaining them. it's like a soldier on a battlefield. you don't know what you're going to be faced with. and on top of that, you've got the fear. "am i going to make it home tonight? " i've never been in fear of my life until now, and we just don't get paid enough to have that fear every day. and there's a lot more detail about the pressures on the prison system on our website. you can find it at bbc.co.uk/prisons. tam dalyell, the former labour mp for west lothian, has died after a short illness. he was 8a. he'll be remembered for his persistent questioning of margaret thatcher over the sinking of the general belgrano during the falklands war and his campaigning against other conflicts. his family said he had devoted his life to public service. tomorrow is holocaust memorial day, marking the anniversary of the liberation of auschwitz at the end of the second world war. commemorations are being held there to remember the six million jews and others that were murdered by the nazis. our special correspondent allan little has been to auschwitz and met one woman who survived her time there against the odds. 72 years ago this week, soviet troops entered auschwitz. this was not the only extermination camp in nazi—occupied europe. but it was where the evidence was best preserved of the crime that came to be known as the holocaust. on this railway platform, nazi officers separated those chosen to live and work from those sent immediately to die. these pictures showed jews transported here from hungary in 19114. susan pollock, 13, was chosen to live. her mother was sent to the gas. there were no hugs or kisses or embrace. the dehumanisation started immediately. i could not cry. it was just as if i had lost all my feelings. that was auschwitz. this was not german crime alone. these railway lines extended to almost every corner of europe, and to the active collaboration of norwegian civil servants, french police, polish train drivers, ukrainian paramilitaries. when it was over, a great public silence descended on europe. after the war, the nations of europe were so preoccupied by their own victimhood that they did not pay much attention to the uniqueness of what had happened here. the jews who survived found that the world beyond these perimeterfences did not want to hear their stories. it was only really in the 1960s, nearly 20 years after the liberation of auschwitz, that popular consciousness began to confront what europe collectively had done to itsjews. international law changed immediately. at the postwar nuremberg trials, two new crimes entered the judicial lexicon for the first time, crimes against humanity and genocide. before 1945, if a state wished to kill half its population, there was no rule of international law that said you could not do that. the change that occurred, as we know sadly, has not prevented horrors from taking place, but it does mean that when horrors occur, there is now at least an objective standard which says to governments that as a matter of international law you cannot do what you are doing. it took half a century for those powers to be used. but dozens have been convicted and jailed by international courts for genocide and crimes against humanity in bosnia, rwanda and elsewhere. even so, holocaust denial persists. the internet is full of claims that the destruction of the jews never happened. but the testimony of survivors is a warning to posterity, to us here today. we are not talking about barbarians, primitive society. the germans were advanced, educated, progressive, amongst the european nations. maybe the civilisation is just a veneer. i think we all need to be very careful about any hate propaganda, because it has got the potential to erupt, and then it is too late to stop it. it's considered to be one of the leading international prizes for contemporary art. held every two years, artes mundi was founded in 2002. and within the past hour the winner of the £40,000 prize has been announced at a ceremony in cardiff. the celebrated british artist and filmmakerjohn akomfrah was chosen from a shortlist of six. here is the winner of the 2017 artes mundi. it is a film, but not of the oscar—winning variety. it's more a series of vignettes, reflecting on the harrowing nature of forced migration. it's by the ghanaian—born, london—based artistjohn akomfrah, whose own family were forced to flee persecution, and like millions today, experienced what it can feel like to move to another country. imagine this, if you're a child of migrants, you sort of live with this, and if you've lived for as long as i have, you've heard this for awhile. i remember this conversation in the ‘60s. which conversation? conversations about whether or not there were too many of you here, the numbers of you. it's such a tragic topic and then, when you pull it into art, you give it a sort of sheen of beauty. does that concern you? yes and no. i don't always do things which are beautiful. but, i mean, i don't shun itjust because the subject's tough. in fact, that's the reason why you bring to bear certain formal questions, to think about ways in which you can make something which feels to people outside of it like, i wouldn't touch that, i wouldn't watch that, as a sort of prelude, as a kind of an invitation. other artists taking part in the prize include the french algerian neil beloufa and american amy franceschini. among the judges was a curator deemed by one publication to be