Thanks for staying with us - we're now wrapping up our live coverage of the coronavirus outbreak across the globe.

Some of the key developments from Tuesday:

• Global cases of coronavirus surpassed 850,000, with 42,000 dead. Meanwhile, more than 177,000 people have recovered
• The death toll in the US passed the figure reported in China, where the outbreak began. At least 3,400 have died

• The White House says about 100,000 to 240,000 deaths are expected in the US due to the outbreak, with President Trump warning of a "very, very painful two weeks"
• A 13-year-old boy is thought to be the UK's youngest victim of the coronavirus outbreak. Ismail Mohamed Abdulwahab, from Brixton in south London, died in hospital early on Monday
• A UK government minister said the country has to go "further, faster" to ramp up its testing capacity for coronavirus
• Stock markets around the world suffered historic losses in the first three months of the year amid a massive sell-off tied to the coronavirus

Join us again on Wednesday when we'll be back to bring you the latest developments, updated analysis and key information to help you keep safe and healthy.

Anthony Zurcher
BBC North America reporter

Image source, Getty Images

There was no sugar-coating it this time. No optimistic talk of miracle cures or Easter-time business re-openings. There was just the cold, hard reality of the facts on the ground.

“I want every American to be prepared for the hard days that lie ahead,” a grave-faced Donald Trump told the nation on Tuesday afternoon. "This is going to be a very, very painful two weeks."

How painful? The number of deaths, based on current projections, is between 100,000 and 200,000.

Mr Trump tried to frame this news as best he could, noting that the projections for US casualties if the government had done nothing were in the millions.

“A lot of people were saying 'think of it as the flu', but it’s not the flu,” he said. “It’s vicious.”

Of course, it was just a week ago the president himself was making exactly such comparisons, noting that the early fatality numbers were much less than those from the flu or even automobile accidents.

Now, however, the seriousness of the situation has hit home. He spoke of checking in on a friend who was in the hospital with the virus - "a little older, and he’s heavy, but he’s tough person" - only to find out he was now in a coma.

“I spoke to some of my friends, and they can’t believe what they’re seeing,” he said.

Image source, Getty Images

Trump’s change of attitude also extended to some of his recent political feuds. Just days after attacking Democratic Michigan Governor Gretchen Whitmer, mocking her name and calling her incompetent on Twitter, the president said he had a “really great conversation” with her and detailed the support the federal government was providing her state.

On Friday, he had suggested that if state leaders were not “appreciative” of him, he wouldn’t talk to them. On Tuesday, he recounted conversations with Democratic governors in California and Louisiana.

The new call from the White House was to continue the current mitigation efforts for an additional 30 days; that even if things go from bad to worse in the weeks to come, the efforts will pay off. It will, however, be a long, slow grind.

CNN reporter Jim Acosta asks if Mr Trump had "lulled the nation into a false sense of security" by downplaying the dangers in the early days of the virus.

"It's going to go away," Mr Trump responds, adding "hopefully by the end of the month". He says he was always aware of the severity of the virus, ever since its early days in China.

In fact, at the time, Mr Trump compared the illness to the seasonal flu, despite health workers saying coronavirus was far more deadly and contagious.

Mr Trump now says he did not want to panic people because "I want to give people a feeling of hope."

"I want to be positive. I don't want to be negative," he says, calling the virus, "the worst thing probably that this country has ever seen".

So far, much of the press briefing has focused on the projected number of deaths, and the importance of mitigation measures like social distancing.

But some politics has crept in too. Mr Trump has praised himself for his response to both the impeachment trial, and the outbreak.

Mr Trump says that his impeachment, which was finalised in early February, was a "distraction" from coronavirus.

But he adds that it did not "divert my attention" from the pandemic, and that his response would not have changed.

"I think I'm getting A pluses for how I conducted myself," during the impeachment trial he says.

"I don't think I would have done any better had I not been impeached... Maybe that's a tribute to something. Maybe it's a tribute to me. But I don't think I would have acted any different."

White House experts are asked to comment on whether more lives could have been saved if mitigation efforts, like social distancing, had begun earlier.

But Dr Fauci and Dr Birx both say that question is essentially impossible to answer - because it is impossible to know whether the virus was already present in the US earlier in the year, that could have been prevented from spreading.

"If there were covert infections here that we didn't know about and we didn't mitigate, it would have made a difference," Dr Fauci says.

"But I believe that we acted very very early there."

Mr Trump says hydroxychloroquine, an anti-malaria medication that he has touted as a possible cure to Covid-19, "would be a game-changer".

Dr Fauci stressed that it was one of many drugs being tested, but those drugs are "generally drugs that already exist for other things".

"There's a whole menu of drugs and interventions that are now going into clinical trials, that are not approved for anything yet," Dr Fauci says.

Mr Trump says the first question he asks of officials everyday is the progress on testing for a vaccine.

Mr Trump says the projected numbers of coronavirus deaths are "sobering", especially as 100,000 is a "minimum number".

"One hundred thousand, according to the modelling, is a very low number," he says.

Mr Trump has criticised those who want to "ride it out".

He says "a lot of people were asking" whether Covid-19 was comparable to the flu, "and I was asking that also".

"But its not the flu. It's vicious."

Mr Trump has been criticised for downplaying the pandemic for weeks, and saying that it may pass by like the seasonal flu. On 24 March, he told Fox News that "we've never closed down the country for the flu."

One ongoing area of debate in the US has been whether the general public should wear masks when they leave home. Current advice from the World Health Organization and the Centers for Disease Control (CDC) is that members of the public do not need to wear masks unless they are ill, or caring for someone ill.

However, earlier today, Dr Fauci told CNN that once there are enough masks in supply for healthcare workers, it might be time for the US public to begin wearing masks outside their home as well. He said the issue would be discussed at today's White House coronavirus taskforce meeting.

Mr Trump was just asked about the subject at the press briefing, and said: "You can use a scarf, scarfs would be very good."

"It's not a bad idea. At least for a period of time," he continues, adding: "And eventually it'll be gone. Hopefully gone for a long time."

Dr Fauci says that the lower end of the projected number of deaths in the US, 100,000, is already based on mitigation measures being put in place - but that he still hopes "we can influence this to varying degrees. We want to do much much better than that."

Meanwhile, Mr Trump has been stressing the importance of mitigation measures.

The question, he says, is "what would have happened if we did nothing", and just decided to "ride it out?"

"I think from a practical standard that couldn't have been carried out", he says, because models forecast that if the US did not undertake any mitigation efforts at all, "that number [of deaths] becomes 1.5m up to 2.2m, and even beyond."

Image source, Getty Images

Dr Birx, the White House coronavirus co-ordinator, says projections show between 100,000 and 200,000 Americans could die due to Covid-19.

"We think that that is the range,” she said, adding that projections are based on some citizens still not doing everything they can to control the spread of the virus. "We really believe, and we hope everyday, we can do better than that."

Dr Fauci also reiterated that the task force would "do everything we can to get it even significantly below that".

Dr Fauci continues: "As sobering a number as that [100,000] is, we should be prepared for it. Is it going to be that much? I hope not and the more we push on mitigation the less likely it would be that number.

"But being realistic, we need to prepare ourselves... It will be difficult – no one is denying we are going through a very difficult time right now."

Deaths from coronavirus are expected to continue into June, according to White House projections. Dr Fauci points out that "deaths always lag", even when the number of new cases begins to slow.

Image source, Getty Images

Dr Anthony Fauci, the US infectious diseases chief, says in the next several days or week, the nation will see cases rise - but the data shows "mitigation is actually working and will work".

"Our goal, which I believe we can accomplish, is to get the hot spot places - New York, New Jersey - and help them to get around that [peak] curve but as importantly, to prevent those clusters of areas that have not yet gone to that spike to prevent them from getting that spike.

"The 15 days of mitigation that we had clearly have had an effect, though it's tough to quantitate it."

Dr Fauci ends by saying the containment measures over the next 30 days should be done with "all the intensity and force that we can".

We can bring you an update on the news of the 13-year-old boy who died in London after testing positive for coronavirus (see our post from 20:51).

The boy, named Ismail Mohamed Abdulwahab, died in King's College Hospital, south-east London, early on Monday.

He is thought to be the youngest person to have died with the virus in the UK.

Ismail's family said they were "beyond devastated" by his death, according to a statement released by a family friend.

They said he had no apparent underlying health conditions and tested positive for Covid-19 on Friday, a day after he was admitted to King's College Hospital.

Mark Stephenson, college director at the Madinah College where Ismail's sister works, has set up a fundraiser to pay for the funeral costs.

A statement on the page said Ismail died "without any family members close by due to the highly infectious nature of Covid-19".

Image source, Getty Images

"No one has been turned away, no one who has needed ventilation has not received ventilation," says Dr Birx of the outbreak in the US, adding that it's been extremely stressful for health systems and those dealing with this crisis firsthand.

"I know its stressful to follow the guidelines but it is more stressful and more difficult to the soldiers on the front line," she says.

"There's no magic bullet. No magic vaccine or therapy. It's just behaviours - each of our behaviours translating into something that changes the course of this viral pandemic over the next 30 days."

Dr Deborah Birx, one of the experts on the US taskforce, says one prediction model shows that if everyone follows the distancing guidelines, it takes the US down to 100,000 or 200,000 deaths - "which is still way too much".

Dr Birx says seeing the case rates in Washington and California, which are far lower than New York, is promising - and is why the US must adhere to strict rules to combat the virus.

"I know it's a lot to ask," she says.

"Every one of us has a role to play in winning this war," Trump says. "Every citizen, family, and business can make the difference in stopping the virus. This is our shared patriotic duty.

"Challenging times are ahead for the next 30 days and this is a very vital 30 days," he says.

He adds that "only good things can be said when you look at the job that’s been done".

Trump says the US government is sending planeloads of supplies to help communities and offers prayers for those helping others and fighting for their lives.

"The country has come together like I've never seen it before," he adds. "We will prevail, we will win and hopefully it'll be in a relatively short period of time."

Trump begins by detailing the equipment the federal government will be sending out to states.

This includes hundreds of ventilators as well as field hospitals that will be set up by the Army Corps of Engineers.

Trump also says since 29 January, over 25,000 Americans have been repatriated from more than 50 countries where they were, "in some cases, locked in".

"I want every American to be prepared for the hard days that lie ahead," the president adds.

"We're going to go through a very tough two weeks and then hopefully, as the experts are predicting...we're going to start seeing some real light at the end of the tunnel. But this is going to be a very painful, very very painful two weeks."

US President Donald Trump is speaking now at the White House as the daily coronavirus task force briefing begins.

The nation now has over 181,000 confirmed Covid-19 cases and has seen 3,606 deaths so far.

An asylum seeker living in a migrant camp in Greece has tested positive for coronavirus, becoming the first known refugee in the country to do so.

The woman was diagnosed with Covid-19 after giving birth at a hospital in the Greek capital, Athens.

Greek authorities are tracing her recent contacts but believe she may have contracted the virus in hospital.

The woman's baby has been tested, with results pending.

She had been living among around 2,500 people at a migrant camp on the Greek mainland.

There have been no cases of coronavirus at the camp, where an isolation area is available, a Greek migration ministry official told Reuters news agency.

Greece has reported 1,314 cases and 49 deaths from coronavirus so far.

Human rights groups and medical charities have raised concerns about the risk of the coronavirus spreading rapidly in overcrowded and often squalid migrant camps in Greece.

Medical charity Medicins Sans Frontieres (MSF) has called on the Greek government to evacuate all its migrant camps immediately.

In Moria in Lesbos, 18,000 people are staying in a facility built for 3,000.

Young filmmakers have sent the BBC footage of conditions at the camp, which can be seen in the video below.

A number of big banks in Britain have agreed to ditch payouts to shareholders in the face of the coronavirus outbreak.

The banks - including NatWest, Santander, Nationwide, the Royal Bank of Scotland, Lloyds, Barclays, HSBC and Standard Chartered - will suspend dividends and share buybacks until the end of the year and cancel outstanding dividends from 2019.

The Bank of England's Prudential Regulation Authority said it also expected banks not to pay any cash bonuses to senior staff.

The PRA said this was a "sensible precautionary step given the unique role that banks need to play in supporting the wider economy through a period of economic disruption.

"We do not expect the capital preserved to be needed by the banks in order to maintain adequate capital positions, but the extra headroom should help the banks support the economy through 2020."

You can read more about ths here.

The daily US coronavirus task force briefing is due to begin in the next half-hour. You'll be able to watch and follow it live here on this page.

President Donald Trump and his team are expected to offer details on the data that led to the extension of containment efforts until, at least, the end of April.

Yesterday, the president told reporters he had been informed that up to two million Americans could die in a worst-case scenario.

We'll soon get a closer look at those models.