Unsurprisingly, Boris Johnson's move to intensive care leads all the UK newspapers' front pages.

Have a quick canter through what they're all saying in our paper review, here.

Dr Deborah Birx, the coronavirus response co-ordinator for the White House, urges the American public to minimise their trips outside, "out of respect" for healthcare workers risking their lives to treat those infected.

"Out of respect for them, we should be doing everything possible," she says.

She urged families to "consolidate" their trips outdoors, saying the "entire family doesn't need to go on separate occasions" because it's a "highly transmittable virus. We want every American to know that what they're doing is making a difference. Maybe, once every two weeks we can do a grocery store or pharmacy shop for the family."

Image source, AFP

Image source, Getty Images

Prime Minister Boris Johnson has asked his foreign secretary, Dominic Raab, to deputise "where necessary".

But the UK has an unwritten constitution, so the formal rules of what should happen if the PM becomes incapacitated are unclear.

Would Mr Raab be allowed to make cabinet appointments, for example? And would he be allowed to control the UK's nuclear missiles?

Our political analyst, Peter Barnes, has some ideas about how things might play out.

You can read them here.

President Trump says "nobody has done more testing" than the US, and that "in my opinion... we have more cases because we have more testing" compared to other countries.

While US testing numbers have greatly increased in recent weeks, it's not strictly accurate that the US has tested more than all other countries if population size is taken into account.

Mr Trump says the US has conducted 1.79 million tests. The US has a population of about 329 million - so that comes out to around 0.5% of the population.

South Korea, which began widespread testing from an earlier stage and has a population of 51 million, says it has conducted 466,804 tests, which amounts to about 0.9% of the population.

President Trump was asked to comment on a row in the Navy, after the captain of the USS Theodore Roosevelt, Brett Crozier, was fired for sending a letter urging Navy officials to help halt a coronavirus outbreak on board the aircraft carrier.

The acting Navy Secretary Thomas Modly said on Sunday that Capt Crozier was “too naive or too stupid” to command the ship.

Mr Trump said “that was a rough statement” from Secretary Modly, but “the letter shouldn’t have been sent”.

He added that he had “heard very good things about both gentlemen” and that he “may just get involved… believe it or not I’m good at settling arguments”.

President Trump says he had a positive phone call with former US Vice-President Joe Biden, the Democratic White House candidate who looks likely to challenge him in November's election.

We "had a really wonderful, warm conversation... he gave me his point of view and I fully understood that. We just had a very friendly conversation, which lasted probably 15 minutes, and it was really good... I appreciate his calling," says Trump.

Joe Biden's campaign said Mr Biden "shared several suggestions for actions the administration can take now to address the ongoing coronavirus pandemic".

However, when asked for details, Mr Trump refrained from giving specifics, only saying he didn't necessarily agree with all of Mr Biden's suggestions.

President Trump said the US had "now performed 1.79m tests" - adding that "nobody has done more testing" and that he believed the US had "more [coronavirus] cases [than other countries] because we have more tests".

The US has lagged behind other countries in testing until recently. President Trump also highlighted his administration's efforts to help state governments, maintaining that some governors sound "very happy" during discussions with his administration.

"They may see you [the media] and say 'ooh, we're not happy' - but they're very happy on the phone," Mr Trump said.

He has recently hit back at Democratic state governors who have criticised the federal government's response to the outbreak.

Image source, WCS

A few hours ago we reported that Nadia, a four-year-old tiger at the Bronx Zoo, had tested positive for coronavirus.

The zoo has given an update and it seems that Nadia and six other big cats showing symptoms are on the mend.

"A little TLC by the keepers taking care of them, some anti-inflammatory medications," Paul Calle, chief veterinarian for the Wildlife Conservation Society's Bronx Zoo, told Reuters.

He said all had mild illnesses and were likely to recover.

Nadia was the only one tested because veterinarians wanted to minimise the number of animals they anaesthetised.

There have been cases of pets contracting the virus but experts say there is no evidence they can spread the disease.

Here are more updates from President Donald Trump's press briefing with the coronavirus task force.

Mr Trump said he had agreed with the New York Governor Andrew Cuomo's request that the USNS Comfort - a navy hospital ship - could be used to treat coronavirus patients.

He also highlighted efforts to distribute and produce more personal protective equipment for health workers - saying government departments had distributed 1.7m N95 respirator masks, and 26.5m surgical masks. He also said he had reached an agreement with 3M, a major mask manufacturer whom he had a row with last week, to supply 165m masks for frontline healthcare workers.

Trump said he was "being told most of the critical needs are being more than met".

However, a US government report published today, external said that hospitals were experiencing "severe shortages of testing supplies" and "widespread shortages" of personal protective equipment (PPE), while an AP news investigation, external said that the government waited until mid-March to place bulk orders of protecting equipment - losing almost two months of valuable time.

More than 10,000 people in the US have died from coronavirus, and some local officials say they are struggling to store and bury the bodies.

In New York City, the chair of the city council's health committee, Mark D Levine, tweeted that hospitals are now forced to rely on refrigerated trailers to hold bodies. The city was preparing contingency plans in case the death rate didn't fall, including temporarily burying bodies in a local park, he said.

The tweet caused a stir, and since then, the mayor's office has said it is not currently planning to use local parks as burial grounds, but is exploring using Hart Island for temporary burials instead. The island is an uninhabited strip of land north-east of the Bronx which is used for mass burials.

Meanwhile, in New Orleans, which has over 4,560 cases and 170 deaths, the mayor has asked the federal government to provide more refrigerated units to store bodies, because morgues, coroners officers and funeral homes are overwhelmed.

One funeral director told Nola.com, external: “I’ve been a funeral director since 1962, and I’ve never seen this.”

Image source, Reuters

The White House coronavirus task force briefing has begun.

President Donald Trump begins by saying America "sends prayers to the people of New York, New Jersey and the whole country".

Then he expresses his concern for UK Prime Minister Boris Johnson, saying he wants to "send best wishes to a very good friend of mine and a friend of our nation".

He says he was "sad to hear he was taken into intensive care a while ago. Americans are all praying for his recovering, he’s been a really good friend". He adds that Boris Johnson is "resolute, doesn’t quit, doesn’t give up".

He adds: "We've contacted all of Boris's doctors... when you get brought into intensive care, that gets very, very serious."

Laura Kuenssberg
BBC political editor

After a day in a strange vacuum, an official statement emerged from Downing Street just after 20:00 BST.

Having struggled to shake off symptoms, and having been taken to hospital 24 hours before, the prime minister had been moved into intensive care, No 10 announced.

It has been clear for many days that Mr Johnson was taking far longer to recover than had initially been expected.

He regularly popped up on social media to say - in customary bombastic tone - that he was suffering mild symptoms and was following advice.

Even this morning No 10 was insisting that he was still receiving red boxes full of government business and was in touch with his team.

But obviously, with his health deteriorating on Monday afternoon, the view of his condition changed.

Read more from Laura here.

Foreign Secretary Dominic Raab, who is standing in for Boris Johnson, says the government is working to carry out the prime minister's decisions.

The pound dropped against the dollar and the euro on Monday after the news that the British prime minister had been admitted to intensive care in a hospital in London.

"Markets hate uncertainty and this does not bode well for further steps in battling COVID-19 and for future Brexit trade negotiations," explained senior market analyst Edward Moya at Oanda Corporation.

More well wishes are being tweeted for Boris Johnson - including from Canadian Prime Minister Justin Trudeau, who wrote, external: "Hope to see you back at Number 10 soon."

Michel Barnier, the EU's chief Brexit negotiator, wished him a "speedy recovery, external", as did EU Commission President Ursula von der Leyen, who also sent thoughts to Johnson's family, external.

And the Archbishop of Canterbury Justin Welby, the most senior cleric in the Church of England, invited the public to join in prayer.

The front pages of the UK newspapers are starting to be published, and, perhaps unsurprisingly, they all focus on Boris Johnson's admission to intensive care.

Here are some of the headlines:

Image source, Reuters

While Boris Johnson has been unwell with coronavirus, so has his fiancée, Carrie Symmonds.

She confirmed via Twitter over the weekend that she had spent a week in bed with the main symptoms, isolating away from the PM, but said she felt "stronger" and was "on the mend".

However, she also had the extra concern of being pregnant.

The couple announced in February they were expecting their first child together in the early summer, and were engaged.

She said having coronavirus while being pregnant was "obviously worrying", but advised other expectant mothers to follow the "reassuring guidance" from the Royal College of Obstetricians and Gynaecologists, external.

Guto Harri, Boris Johnson's communications director when he was mayor of London, has spoken to BBC News.

"There has tragically been quite clearly a deterioration that is quite significant for him to now have to succumb to intensive care and to have to deputise formally to the foreign secretary," he said.

Mr Harri said in the four years he worked for Mr Johnson, "I don't think he was ill once" and said the PM would be "hugely frustrated" that he cannot now take the lead.

"I think what's clearly happened over the last few weeks, there have been enormous decisions about lives and livelihoods… and he'd have felt that the important thing was he was out there, he was seen to lead from the front and he probably wouldn't have slept well and would have been working too hard."

The White House coronavirus task force is due to give its daily press briefing shortly. President Donald Trump nearly always speaks at these briefings, as do Vice-President Mike Pence and health experts Deborah Birx and Anthony Fauci.

Last week, the White House used the briefings to explain government projections that the number of coronavirus deaths could range from 100,000 to 240,000, and to discuss new guidance that advised all Americans to wear cloth face-coverings in public.

Mr Trump has recently been urging the public to take the outbreak seriously - although critics have also accused him of using the briefings as a political platform.

Image source, EPA

Boris Johnson was given oxygen before being taken into intensive care on Monday afternoon, the BBC's Chris Mason reports.

Not much has been released as to the prime minister's condition, but Number 10's statement earlier said he had "worsened" after suffering persistent symptoms of the coronavirus.