>> part of al jazeera america's >> special month long evironmental focus fragile planet today, the united states together with our allies and partners has reached a historic understanding with iran. >> a nuclear agreement between world powers and iran after decades of negotiations. good to have you with us. you're watching al jazeera live from london. also coming up in the next 30 minutes, al shabaab gunmen kill 147 at a kenyan university. more students are still unaccounted for.

the saudi-led coalition says it's determined to rid the southern city of aden of houthi rebels who they say now are isolated. a drought forces california's governor to order a 25% cut in water consumption. iran and six world powers have reached an understanding which it's hoped will lead to a comprehensive nuclear deal in three months. it would limit iran's nuclear enrichment to one site only and also reduce its stock pile to 300. in return the eu and u.s. gradually will start to lift nuclear related sanctions after inspections by the iaea the

international atomic energy agency. the aim is for a new deal to be completed by june 30th and it should include a u.n. security council endorsement. the european union's foreign policy speech started by detailing iran's side of the deal. >> as iran pursues a peaceful nuclear ram, iran's enrichment capacity level, and stock pile will be limited for specific durations, and there will be no other enrichment facility. iran's research and development on centrifuges will be carried out on a scope and schedule that's been mutually agreed. international collaboration will be encouraged in agreed areas of

research. there will. >> it all includes significant financial and economic sanctions relief for iran. the foreign minister of iran welcoming the agreement to end all u.n. security council sanctions against iran. >> it will be the end of security council resolutions that have been adopted against iran. now, there will be certain limitations that some countries wish to impose against the islamic republic and those limitations, we do not -- which do not include limitations in areas of finance, trade, and economy and may include from their perspective proliferation areas may continue for a brief period of time and then suspended and terminated. >> well we have our correspondents in switzerland where those talks have been

taking place and in washington d.c. our diplomatic editor. these have been marathon sessions but it is not as simple as saying no nuclear bomb no sanctions. there's a long long way to go yet. >>reporter: there is a long way to go and there really is a lot of detail to look at here. and also the detail of actually what this is. the obama administration had promised that it was going to come up with a framework agreement. that was the word. when the foreign minister of iran was asked about this he said there is no agreement yet there are no obligations on anyone. this is just an understanding of where we are going. so they certainly have come up with quite a lot of detail and at some points in the very very long negotiations that have taken place here there was the

possibility i think where there could have been a breakdown. on this particular session here they have been here for eight days. that followed a break of just a couple of days and before that six days of negotiations. and just in the last 24 hours, we've seen pretty much nonstop meetings all around the clock. they negotiated to try to get these details agreed overnight at one point in a series of meetings for nearly nine hours. john kerry and the iranian foreign minister sitting around the table at one point. i was told it was very hard to try to negotiate when you're so sleepy. but through all of that they've come up with quite a detailed program. i mean there's a lot of detail in here although the question is whether it's binding on anyone. the main deadline coming up on june 30th. >> what we're hearing is that

there will be no movement on sanctions until then. just a line here from john kerry. we will make absolutely certain that all pathways to make a nuclear weapon have been cut off. he also said we're going to -- ten, 15 25 years. but this is an indefinite agreement and we can all times put those sanctions back in. >>reporter: absolutely. although i think the u.n. security council has had disagreement on that. both kerry and obama using the phrase "snap back" but russia and china don't like the idea. so i still think after

june 30th, even if they get that deal on june 30th there's still going to be work to be done on the u.n. security council to lift those sanctions and maybe some disagreements there. the other sanctions, the eu and u.s. sanctions, they eventually will be lifted on the economic aspects affecting iran. >> okay. an awful lot of work still to be done but i think everybody would agree that it has been a monumental announcement within the last hour or so. the u.s. president, barack

obama, having delayed a trip to one of his states. he says he called the deal when he got to the white house lawn historic. >> the united states together with our allies and partners has reached a historic understand with iran which if fully implemented will prevent it from obtaining a nuclear weapon. as president and commander in chief, i have no greater responsibility than the security of the american people. i'm convinced that if this framework leads to a final comprehensive deal, it will make our country, allies and our world safer we are now live at the u.s. capitol. clear up a couple of things for us. if a deal hasn't been reached this week a frame work deal nothing final about it were those in congress who were saying we want to increase rather than decrease the

sanctions, has that now gone away? >> we have not heard much about the sanctions. that seems to be on the back burner. but we've already heard from the republicans in charge of the senate and he says on april 14th when they're back in session the foreign relations committee is going to take up his bill which would demand that the president bring the deal to congress and that they can approve it or say no. it's not clear that the president can keep enough democrats on board to not override this veto. the american people in the latest polls show that in fact

the vast majority want to see a deal made. the president has a strong case to make to the american people and signalled today that he's going to send that message to the people. >> when we heard from the head of the foreign relations committee that congress needs to be able to weigh in on this is -- we're going to have our say on this and if we don't like it, we can still er it all. >> exactly. it gives them -- and then they do have the final say. the american people also say that they think congress has a role to play in this but we're seeing some of the top democrats right now saying let's look at the details of this deal. the president in his speech i want to point out was sending messages and unless you follow the argument quickly you may not realize he was trying to counter what are going to be the

negative comments. one of the biggest complaints from republicans on sanctions is that if sanctions are lifted iran will have a lot more money to give to groups considered terrorists. another complaint is timing. you heard secretary kerry say there's no sunset. basically saying they're never going to have a nuclear bomb and the other issue and i think this got lost in the statement is that iran says they're going to clarify past and present issues. that's been a big deal here in the united states because don't forget the iaea says it still can't verify the military aspects to what iran had been doing in the past.

so he's making this case to congress and his main argument is going to be if you want war, then say no to this deal and he's going to tell the american people that's what congress will be doing if they scuttle the negotiations. >> 21 months in my calculation that obama has left in the house behind you at 1600 pennsylvania avenue. there were a lot of people who figured he would be a lame duck president. if this comes off, he would look at it in terms of being a crowning glory as major foreign policy achievement after eight years in office.

he's still being cautious. i think one point we need to research a little further is if congress did say no to deal it's not at all clear that the other powers at the table couldn't in fact continue to have an economic relationship with iran which the white house is going to argue will only alienate the united states and not iran. >> all right. thank you very much indeed.

a siege at a university in kenya has ended up in blood shed and a rising death told. at least 147 students have been killed killed. four gunmen have also been killed. the al quaeda-linked al shabaab group from somolia has claimed responsibility. >>reporter: it was supposed to be a place of learning but instead became a battle ground. kenyan troops tried to flush out al shabaab fighters holed up inside the university. they stormed the building in the early hours of the morning while students were sleeping. [sirens]. >>reporter: security forces were deployed. it's close to kenya's board with

somolia and has been targeted before by al shabaab, a somali based group linked to al quaeda. some students were taken hostage and others managed to escape. >> it's unfortunate that where they're going is where the gunshots are coming from. >>reporter: within hours, al shabaab said it was behind the assault. many of the injured suffered gunshot wounds. and inside the hospital where they were treated, pain grief, and horror. [crying]. >> we were praying and were about to finish when some people came in from the main door and started shooting. they started shooting. there was one gunman firing from the doorway so i had to jump from the window and that's when i was hit in the leg. >>reporter: this attack will undoubtedly lead to questions about whether enough security was being provided at the university. >> 90% of the threat has been

eliminated as a speak to you now. of course a very very heavy cost. human life was lost. as it stands now, we are able to rescue over 500 students. >>reporter: a dusk to dawn curfew is now in place. kenyans once again trying to terms with the loss of so many. let's join malcomb webb our correspondent in kenya just outside the university. do we know for sure malcomb, that it is over? >>reporter: that's what we're hearing now. we've just spoken to some people who have been inside or near the university compound this evening. they said that they've now started taking out their bodies from there and taking them to

the morgue. the internal affairs minister gave a press conference just a short while ago and confirmed that they said the total number of people killed is 147. and this is what we heard from some of the hostages we spoke to on the phone who said there were dozens and dozens of bodies by the time the shooting had stopped. >> many people will be critical of kenya and its security operation not being able to protect people in the north but the truth is that this is a very long border and is almost impossible to police isn't it? >>reporter: it's true. yes. it's very open terrain, not densely populated, and it seems al shabaab pretty much have freedom to move around and launch attack when is they want to. it is difficult to control this area but some people in this town we've heard from reliable

sources have expressed concerns and approached the government and said something should be done about the security at the university given the area is insecure anyway and al shabaab it seems can launch attacks in this part of the country. they said the university is particularly vulnerable because it's a concentration of young people living there and many of them are actually not from this part of the country. this part of the country, most of the people here are ethnic somalis. al shabaab generally in their attacks target kenyans of other ethnicities from other parts of the country. so you have a lot of non-somali kenyans concentrated in this small area with just two guards at the gate. people have asked security to be increased and that didn't happen and it turned out the university was very vulnerable. it seems a group or four or five

or maybe six attackers managed to cause all this havoc and kill a total of what we as far as we know is 147 people. >> thank you. malcomb webb in the north of kenya kenya. let's bring in the executive director of the african immigrant caucus joining me live from washington. is it true that both of the u.k. and awes -- awes trailustralian government warned them of this even as early as a week ago? >> i was told they dismissed them and said if too many funds

are fed to this it will affect tourism. so that is what i have read. it is hard to believe so i want to look into it further. >> what about the suggestions, particularly from somali government people that i have spoken to that al shabaab is pretty much -- does this give a light to that? is it still a very very effective force even if it happens to be across the border in kenya? >> you know i think, i think it fits with what i know of how groups like this operate. now, i must quickly say that my focus is on foreign policy and international relations with africa. i'm not a security expert. but it seems to me actually groups are losing places and land that they control, they then start taking these kinds of out of the blue isolated

terrorist -- isolated terrorism incidents. i believe that they seem to be losing the amount of territory that they were controlling in somolia. they are losing -- this fits with that in my mind. >> thank you. houthi fighters have reportedly made a key gain in yemen's southern coastal city of aden. rebels are set to have seized the presidential palace. these pictures are said to be -- a strong hold of president hadi. on thursday, the houthis took the commercial center of aden and fighting is still reported to be going on. the attacks on the presidential palace are a major

blow to the saudi-led coalition. saudi arabia has also experienced its first casualty. the interior ministry saying one of its border guard soldiers was killed on the border and that ten other soldiers were injured. and al quaeda is taking advantage of the turmoil to expand its foot hold in yemen. fighters from the group have stormed a prison in the east and freed hundreds of inmates throughing an al quaeda leader. in the last few hours, the saudi spokesman gave an update saying houthi rebels are now isolated in this southern port city. >> we managed to fend off all the houthi fighters in the outskirts of aden and we can say the situation is calm and stable. following the houthi's coup

they took advantage of -- some of the houthi fighters were able to stake station inside the city. yesterday they attempted to seize control of certain government facilities. heavy fighting erupted. such incidents were expected by coalition forces simply because techniques are well known to us that are employed by houthis. they also aim to gain certain media victories, a desperate attempt by houthi fighters totally isolated in yemen. we are in close contact with popular resistance fighters. >> leaders of -- televised debate. the election now just 35 days away. it's happening near manchester. all of the main leaders will face each other during the campaign. two hours and it includes prime

minister david camron. we saw him just then. polls indicate that no one party is set to be able to form a majority government. a russian trawler has sunk killing at least 54 off the coast. the cause is not known. >>reporter: russian authorities are calling it the worst maritime accident of recent years in the far east. a large trawler carrying 132 people turned over and sank in just 15 minutes earlier on thursday morning. at least 60 were rescued by other fishing vessels and a helicopter sent to help. but this catastrophe in the ice cold waters ended the lives of more than 50 sailers.

investigators are already trying to find out why. >> we'll look into the availability and quantity of the life saving equipment. we will look at whether there is a signal that was sent in a timely fashion. and we'll check the crew qualifications and assist the actions by controlling authorities that gave permission for the ship to sail at sea. >>reporter: a criminal investigation has been opened and a number of theories are being examined. possibly it hit something or maybe it was lifting a heavy net with too many weight in its ballast. these pictures show how difficult the water off the russian coast can be especially when the sea is icy. vladimir putin's spokesman said the president is being kept

informed of the rescue operation and messages of condolence have come from the u.s. embassy here in moscow and from the head of the european union's delegation to russia. 13 sailers remain missing but the search has been suspended until first light on friday morning. california's governor has ordered that a 25% cut in water use across the entire state. the reason is that the river is dying. >>reporter: on a late afternoon day, this family is fishing for dinner along the river near fresno california. chances are they won't catch anything. the state's second largest and longest river is dying. topping american river's list of the nation's most endangered rivers. to find out why i met with conservation expert john caine for a kayak trip on the river.

>> the most important reason why the river is in such bad shape today is that it simply doesn't get enough water to be a healthy river. >>reporter: why is that? >> it doesn't get enough water to be healthy because so much water is diverted for agriculture. >>reporter: california's central valley is home to the nation's bread basket. crops that grow here help feed the world with farms large and small making up 7 million acres of irrigated farm land. over the course of its 366 mile run, the river and its tributaries are dammed 73 times. water siphoned helps irrigate harvey bailey's lemon orchard. are you the reason it's so endangered? >> if you want to go back to when it was decided that the water was going to be diverted to go south to benefit a tremendous amount more people and grow crops that go all over the world, you can say that it

was that that killed the river. >>reporter: every day, people drive right over the river. but what you can't see from the bridge is that there's no water here and there has not been for years. if you come down the slope even look this way, this was once a mighty river. at one time there was enough water here to carry steam boats 80 miles up river all the way to fresno. today all you'll find here is plenty of sand couple of shells, and some footprints. and the parts of the river with water are so low that the salmon population has been reduced to essentially nothing.

there are a lot of political forces that would rather just have the water for farms and not worry about the river. we're asking the state water to stand up for the river and protect it. >>reporter: the state water board is the agency in charge of water rights in california. how has it gotten to this point? >> everybody wants these things to happen of course quickly. in the end, many people will not like the specific answer. but what we're going to do in this process is make sure that we're relying upon the best science and the protection of fish and wild life and balance it again with the uses for agriculture. >>reporter: conservationists like john caine say increasing the river's flow even a small amount can balance those needs. >> the river can be saved. the plan only calls for 25% of the river's natural flow to stay in the river. >>reporter: still, even that might be a hard sell during the state's historic drought which

has only made a bad situation worse for boths the farms and the fish so many people rely on. jennifer london al jazeera. and if you care to go online you'll find us streaming, aljazeera.com. that's aljazeera.com. 's aljazeera.com.