this is the business briefing. i'm sally bundock. the us huawei tech ban starts now with government agencies restricted from doing business with it and four other chinese tech companies. market meltdown, the argentine peso tumbles and it's stock market crashes after the country's ruling conservative president loses big in primary elections. and jitters are being felt across emerging markets today with political unrest in argentina and hong kong.

japan have reopened down over 1%. a us ban has kicked in, barring government agencies from buying equipment made by some of china's biggest tech firms. it comes as president trump's national security advisor visits london, while stressing the uk is ready to strike a trade deal with the uk after brexit, he said the involvement of the chinese telecoms firm huawei in building the uk's 56 mobile infrastructure could be put off until after the uk leaves the eu. today's us ban stops government agencies buying from huawei and a host of other chinese firms, including telecoms equipment maker zte, and hikvision, which makes security cameras. huawei in particular has been described as a national security threat, amid fears it could be used by the chinese government to spy, something huawei says

it would never do. but the ban also comes amid mounting trade tensions between the us and china, with america due to impose a 10% tariff on an additional $300 billion in chinese imports on the 1st of september. dr thomas gift, lecturer in political science, public policy, economics and analysis at ucljoins me now. it's nice to see you again. it's an interesting story, because today the band comes into effect in the united states and if feel like we've been talking about this for over a year. it feels like that because we have. this is the enforcement of the national defence authorisation act which was signed into law in 2018 but now is actually taking effect. essentially what it does, it says that us federal government agencies like nasa and the pentagon can't purchase components,

telecommunications, surveillance equipment from highway. it's a big move, but it's not entirely unexpected. and that is one of four companies. private companies in the united states, though, many who have worked in highway in the past, what does it mean for them? the question isa does it mean for them? the question is a good one because it is really unclear. certainly there are facts for companies going to be doing government contracts with the federal government and the federal government itself. but for other private companies, there really is a lack of clarity and that has become one of the big problems. as a result, a lot of these companies will think twice before they actually engage in commercial transactions with highway. how does this player in terms of the us — china relations? well, it's certainly again is kind of an of this trade war that is ongoing. there was some reports that this was a big sticking point in the last negotiations between trump and the

chinese and is one of the reasons why a trade deal didn't actually go through. so it certainly is not good for the relations between these two countries. in terms ofjohn bolton even being in london and talking about trade between the us and uk, i mean, while i was a real issue in discussions between theresa may and the white house. what about now?m seems like there may be a shifting of course, of course theresa may made a provisional stance that highway would be allowed to be involved in the creation of the sg network here in the uk. john bolton has really pushed back against that and the trump administration's really pushed back against that because they think it constitutes a significant security concern. john bolton reported that the boris johnson administration has said they are going to rethink the decision of theresa may, that they are going to start at square one, to quote. so i think that is a fairly significant

shift. we will keep a close eye. thank you for sharing your expertise once again. thank you. and there is more detail online so you can have a further reading if you wish to. now let's go to argentina. argentine stock markets and its currency have both plunged after conservative argentine president mauricio macri suffered a shock defeat in primary elections on sunday. the peso fell 15% against the dollar on monday after earlier plunging around 30% to a record low. some of the country's most traded stocks have also lost around half of their value in one day. 0ur south america business correspondent daniel gallas has more. monday's market meltdown in argentina is likely to have many repercussions in the region. the government tried to intervene in currency markets, but there was no way to avert one of the worst days in the history of argentina's stock

market. primary election results suggest voters in argentina are rejecting the pro—business market reforms implemented by mr president mauricio macri and his deal with the imf, that was to implement austerity cuts and capital controls in argentina. in fact, what these results suggest is that voters want the return of the left—wing politicians who think argentina must dig austerity and spend its way out of crises. a lot of market investors believe that is the wrong way forward and that is why they've been selling their assets on monday. there were also ripple effects in neighbouring countries like brazil that saw a drop in its stock market as well. argentina will hold elections in only two months from 110w elections in only two months from now but the lead established by the opposition is so big now that very few market analysts believe they can lose this election. so by the end of

the year the leftists are likely to oust mr macri. that is daniel gallas. now let's brief you on some other business stories. the uk is "first in line" for a trade deal with the us, president trump's national security adviserjohn bolton says. his comments came after meeting prime minister borisjohnson. according to mr bolton, deals could be done on a "sector—by—sector" basis, with an agreement on manufacturing being agreed first. that is something we have discussed in quitea that is something we have discussed in quite a bit of detail earlier in the programme. hong kong's main airport remains the focal point of pro—democracy demonstrations. that's as authorities say operations have resumed this morning. yesterday afternoon all passenger flights were cancelled as thousands of protesters converged on terminals. the flying car, it's been the pipedream of inventors for more than a century, but none has ever made it

onto the market. could that be about to change? let's take a look at some of the latest and most promising developments. along a highway, the flying car makes its first test. an automobile but also flies. it's a combination of air and car. it's a combination of air and car. it meets all the requirements, all the regulations for both aeroplanes and cars in the united states. you can fit it in your garage, you can

drive it to an airport, you can u nfold drive it to an airport, you can unfold the wings and fly to another airport. folded up and flayed to your destination. —— fold it up and fly to your destination.

really interesting. send us your thoughts about that. as we mentioned, it's pretty tough right 110w. mentioned, it's pretty tough right now. the main market in the us was down by 1.5% as was the snp and that really set the tone for asian markets. —— s&p. and the hang seng is trading down because of the disruptions in hong kong. let's look at the commodity markets briefly. gold still really strong, safe haven is very much in favour at the moment. so that's a look at financial markets and that is your business briefing.

an extra £100 million to improve security at prisons in england and wales has been announced by the government. it's the latest in a number of pledges of money for the criminal justice system. boris johnson says more airport—style measures such as x—ray scanners would stop weapons and drugs getting into jails. june kelly has the story. leeds prison — it's not a top security jail, but like leeds prison — it's not a top securityjail, but like others, it's ina big securityjail, but like others, it's in a big problem with violence caused by drugs smuggled in. in the last year, new measures have been introduced here and at otherjails to try to crack down on this crime behind bars. airport staff security is in place including x—ray scanners and metal detectors —— airport

style. now there are plans to do the same with prisons across the country. the latest in a series of government pledges of money for the criminal justice system. government pledges of money for the criminaljustice system. this is pa rt criminaljustice system. this is part of a package of measures announced in recent days, you've got 20,000 extra police, we've seen £2.5 billion invested in ten new prison places and we've seen this announcement about security. taken together, these take a really strong commitment to law and order —— represent a really strong commitment. an additional technology to block mobile phones, they are supposed to be banned. what it is of a prisoner high on drugs was filmed ona a prisoner high on drugs was filmed on a mobile. it's shameful that prisons have deteriorated so badly that they have become centres of crime and violence and drugs. and the government has good money —— has to put in good money to solve the

problem they have created. and labour has accused the government of tinkering at the edges of a problem caused by austerity. this is the briefing from bbc news. the latest headlines: as hong kong's airport reopens, the region's leader warns violence is pushing them down a path of no return. the trump administration continues to clamp down on immigration, this time targeting people who need government aid. now it is time to look at the stories that are making the headlines in the media across the world. we begin with the times, and this photo of borisjohnson and his partner carrie symonds together at their first joint public engagement. the paper leads on the us, saying it will enthusiastically back a no—deal brexit and work with the uk on sector—by—sector trade agreements. now onto the south china morning post, and chaotic scenes

as thousands of anti—government protesters crippled hong kong international airport yesterday, bringing it to a standstill. the airport has now reopened, but hundreds of flights have been cancelled. the ft reports on the use of facial recognition technology in security cameras in the kings cross area of central london. the paper says the developer for the site claimed the cameras were for public security, but would not confirm how long facial recognition had been active. ministers in the uk are calling for a ban on all mobile phone use while driving, reports the i. it says mps will warn that hands—free kits create the same crash risks as holding a phone. and finally, the metro has this story on a university banning the sale of burgers on campus to help tackle global warming. goldsmiths, university of london, says it will remove all beef

products from canteens and shops next month, thanks to pressure from students who want to make a difference. with me is independent analyst stephanie hare. great analyst stephanie hare. to have you with us today. let's great to have you with us today. let's start with this front—page story. we have already talked about it to story. we have already talked about ittoa story. we have already talked about it to a degree, a picture of boris johnson and carrie symonds hosting an event in downing street for the first time together. but it really focuses onjohn bolton, their discussions, and of course what this means going forward in terms of trade deals for the uk. in many ways it was music to the ears of the new prime minister, wasn't it? just the message he wants to get out