welcome to bbc news — broadcasting to viewers in north america and around the globe. my name is lewis vaughanjones. our top stories: theresa may and eu officials agree "legally—binding changes" to the brexit deal, ahead of a crucial vote in the british parliament. today we have secured legal changes. now is the time to come together to back this improved brexit deal and to deliver on the instruction of the british people. european commission president jean—claude juncker warns voting down the deal would put everything at risk. in politics, sometimes you get a second chance. it is what we do with the second chance that comes because there will be no third chance.

investigators recover the voice and data recorders from the ethiopian air crash. but as more airlines ground the type of plane involved — us aviation officials say they believe it is airworthy. it's been ruled a ""socially harmful cult" by the new south wales supreme court. we track down the group known as universal medicine. welcome to bbc news. we start with the big developments in brexit. the british prime minister has declared legally—binding changes to her brexit deal, just hours before the house of commons is due to vote on it. theresa may has been seeking additional assurances about the irish backstop — the measure to prevent the return of border controls between northern ireland and the republic. she says she now has assurances that the backstop would never be

permanent, if it was ever used. but there was a clear concern in parliament over one issue in particular, the northern ireland backstop. having an insurance policy to guarantee that they will never be a hard border in northern ireland is absolutely right. it honours the uk's solemn commitments in the belfast good friday agreement. but if we ever have to use that insurance policy, it cannot become a permanent arrangement, and it is not the template for our future relationship. the deal that mps voted on injanuary was not strong enoughin voted on injanuary was not strong enough in making that clear. and legally binding changes were needed to set that right. today we have agreed them. first, a joint instrument with comparable legal weight to the withdrawal agreement will guarantee that the eu cannot act with the intent of implying the backstop indefinitely —— applying.

if they are found to be a breach the uk can suspend the backstop. the joint instrument also gives a legal commitment that whatever replaces the backstop does not need to replicate it. and it entrenches in legally binding form the commitments made in the exchange of letters with presidents donald tusk and jean—claude juncker in january. the president of the european commission, jean—claude juncker, warned mps that they would be putting everything at risk if they voted down mrs may's brexit deal. in politics, sometimes, you get a second chance. it is what we do with this second chance at that counts. because they will be no third chance. there will be no further interpretation of the interpretations and no further assurances on the reassurances. if he vote fails tomorrow. let us be crystal clear about the choice. it

is still brexit might not happen at all. there's lots to decipher in the deal. our correspondent, adam fleming was at the joint news conference in strasbourg with mrs may and jean—claude juncker. he explained what it all means. theresa may's last—minute dash it to the european parliament in strasbourg has resulted in a word soup of multiple different documents providing reassurance and clarification about the deal that was done last year. first of all, there was a joint interpretive instrument, which is reinforcing, in legal terms, equivalent to a treaty, that each side will work very hard to agree a trade deal, which means you will not have to use the northern ireland backstop, and if that comes in it would only be for a temporary period, not permanent. is stuff we have heard before, but it is now being put into a form that is the highest legal level the eu can do. then there is going to be an

addendum to the political declaration, that is the document that goes alongside the divorce treaty, which spells out the shape of the future relationship. there is going to be a commitment that you have an extra track in the negotiations that will look at something called alternative arrangements. now they are alternative arrangements for avoiding a hard border in northern ireland, that are not the backstop, and not the future relationship. the idea being that if you don't have a future relationship you go into that, rather than the backstop. there is also a statement that is unilateral only from the uk about its interpretation of all of this. it is quite confusing, even for professional watchers of the brexit process. but what it comes down to is this, is this enough for the uk's chief lawyer, the attorney general geoffrey cox, to change his legal advice and say there is now way probability that it came to the uk could not be trapped forever in the backstop against its will? can he go

from a thumbs down to a thumbs up? and the next big question is, how niemand is parliament does that convince to change their opposition to the dealfor convince to change their opposition to the deal for support for the deal when they vote on it on tuesday? —— how many members? that was adam fleming's stirling effort to explain everything. and you can find analysis of theresa may's agreement with eu officials, on what they've described as "legally—binding changes" to the brexit withdrawal deal on our website — bbc.com/news, or download the bbc news app. us aviation authorities say they believe the boeing 737 max aircraft, of the type that crashed in ethiopia on sunday, is airworthy. both black box recorders have now been recovered. the aircraft was flying to the kenyan capital, nairobi , when it crashed minutes after taking off from addis ababa, killing all 157 people onboard. our correspondent emmanuel igunza sent this report from the scene.

it's a slow, delicate process of recovering pieces of the plane that might offer clues on why flight et302 came down. more remains of those who died have been recovered from the rubble, as rescue efforts enter the second day. the main focus for the investigators has been that huge crater that was made when the plane hit the ground. now, throughout the day, we've seen them pull out debris, including this mangled wreck, here, of what remains of that aircraft. we've also seen them retrieve the black boxes, which will help with the investigations on finding out exactly what happened. the passengers on board were from 35 different countries. nine were british. at least 21 in un staff were also killed. delegates remembered the doctors and academics who died in

the crash. the un secretary general, antonio guterres, spoke about the tragedy. our colleagues were women and men, seasoned officials, hailing from all corners of the globe and with a wide array of expertise. they all had one thing in common, a spirited to serve the people of the world and to make it a better place for us all. it is the second time this type of aircraft has crashed in five months. in october, and indonesian lion air playing came down shortly after take off. today china and indonesia, along with ethiopian airlines, grounded their fleets of the 737 max 8. recovery effo rts fleets of the 737 max 8. recovery efforts are coming to an end, but the investigation into what happens to this flight will continue for many months. emmanuel igunza, bbc news, bishoftu, ethiopia. our north america correspondent

peter bowes is in los angeles. what have the us aviation authorities been saying? they say thisjet is a authorities been saying? they say this jet is a worthy, but they require boeing to make some software enhancements over the next few weeks. boeing have confirmed that since that indonesia crash at the end of october of last year they have been working on those enhancements to the software systems of this particular type ofjet enhancements to the software systems of this particular type of jet and they will be implemented over the next few weeks. so it seems that before this crash in ethiopia that work was in hands. and what the federal aviation administration, the aviation authority here in the states is distressing is that it is very early days in terms of the investigation to see what happened over this past weekend. they say they need to see the dato, they had not seen that they do from the black box, they are sending investigators to work with people on the ground. boeing are doing the same. and that

it is early days in that investigation. and clearly, at this stage, it is impossible to decide that whatever caused this particular plane to crash, the technical problems, if india was technical problems, if india was technical problems, may not be the same as what happened in the crash six month ago. peter, we are in this strange situation at the moment when we have some airlines grounding planes, but others not. yes. on that list of countries grounding planes is grovelling by the hour. ethiopia, indonesia, china, brazil, airlines in those countries and others have decided to ground this particular jet, whereas others haven't. and here in the united states the biggest user of this particularjet, american airlines south—west airlines is indeed the biggest user ofa airlines is indeed the biggest user of a particular kind of plane, they are continuing to fly. for the pass 24 are continuing to fly. for the pass 2a hours have been operating normally. it remains to be seen how quickly these enhancements are made

and the speed of the investigation. everyone will be hoping it moves very quickly. but there are critics, certainly of the aviation authorities here in the states, saying that this wait—and—see policy isn't good enough and that it could potentially lead to further loss of life is indeed these problems occur on another flight. peter bowes, thank you very much for the update. peter bowes in los angeles for