The UK is at the point of “maximum risk” in its battle with coronavirus, Boris Johnson has warned, as he returned to Downing Street to lead the government’s response to the outbreak amid calls to increase testing numbers and begin lifting the lockdown.
The prime minister resumed his full-time duties three weeks after he was hospitalised with Covid-19, insisting he would not risk a second peak in the disease by relaxing restrictions too quickly.
Senior Tories have called for the government to begin lifting the measures over concerns at the damage it is causing the economy, but scientists have warned any relaxation risks a renewed flare-up, with up to 100,000 people dying by the end of the year.
The number of cases worldwide has nearly reached 3 million, according to official statistics from Johns Hopkins University.
Meanwhile, New Zealand was preparing to ease its strict lockdown rules after claiming to have “achieved our goal of elimination”.
Here are the day's events as they happened.
Prime minister returns to Downing Street
Boris Johnson has returned to Downing Street to take charge of the government's response to the coronavirus outbreak, three weeks after he was hospitalised with Covid-19.
The prime minister will chair the regular morning meeting of the government's coronavirus "war cabinet" before heading into a series of meetings with senior ministers and officials.
Mr Johnson arrived back on Sunday evening amid growing clamour from senior Tories to begin lifting the lockdown over mounting concerns about the damage it is causing to the economy.
However, scientists advising the government have warned any relaxation risks a renewed flare up just as the number of patients in hospital with the disease begins to fall, with up to 100,000 dying by the end of the year.
Pressure to begin easing lockdown
The pressure to begin easing the restrictions came from a series of wealthy Tory backers who called over the weekend for the government to allow the economy to re-start.
They echoed former chancellor Philip Hammond who said the country could not afford to wait for a vaccine to be developed, saying the "economy will not survive that long".
Sir Graham Brady, chairman of the Conservative backbench 1922 committee, told BBC Radio 4's Westminster Hour that more needed to be done to get the economy moving, and there was a limit to how long people would tolerate restrictions, especially if they seemed illogical.
He urged an "overriding principle ... that we will only maintain those restrictions which are necessary and if there is a question over whether something is necessary or not, I think we should ere on the side of openness and trying to make sure that more people can get on with their lives and more people can get on with getting back to their jobs".
Labour leader Sir Keir Starmer - while backing the lockdown - added to the pressure with a renewed call for the government to set out an "exit strategy" explaining how it will eventually be lifted.
Boris Johnson preparing for major decision on lockdown review
The prime minister has less than two weeks before the next major decision point comes up with the next three-week review of the lockdown restrictions due on7 May.
His deputy, foreign secretary Dominic Raab, said the government was doing its "homework" in preparation for when the rules could be eased.
It is thought that amongst the first could be a re-opening of schools, although Mr Raab said that would be "inconceivable" without some further measures in place.
Ministers are also thought to be considering allowing some non-essential businesses to open such as garden centres and car showrooms, provided social-distancing could be maintained.
Mr Raab also indicated that officials were looking at possible checks at air and sea ports with passengers arriving in the UK required to quarantine for 14 days.
Such a measure could form part of the next stage of the government's response - the so-called "test, track and trace" strategy designed to further suppress the spread of the disease by isolating new cases.
Calls for staggered shifts and social distancing rules after lockdown
Frances O'Grady, general secretary of the Trades Union Congress (TUC), said she wants to see shifts staggered and social distancing rules continue when the lockdown is eased by the government.
She told BBC Radio 4's Today programme: "Everyone wants people to get back to work safely so we can get the economy back on its feet.
"But workers have to know and be confident that their health and safety is being put first. Otherwise we are going to see the virus spread again and be back to square one.
"We are calling for tough new measures - we think there should be a proper risk assessment on the virus in every workplace, that we need practical changes like social distancing, staggered shifts, safe transport.
"And we need those risk assessments signed-off by unions or health and safety inspectors, with tough enforcement and the resources to do that tough enforcement."
Ms O'Grady said the issue should be at the "top of the prime minister's in-tray" now that he has returned to work.
Measuring blood oxygen could help with early detection
Professor Babak Javid, a consultant in infectious diseases at Cambridge University, said measuring blood oxygen levels could help with early detection of those experiencing coronavirus symptoms.
He told BBC Radio 4's Today programme that a low level of oxygen in the blood was a sign of Covid-19 - a symptom that could be measured with a pulse oximeter.
A "danger sign" was if oxygen levels dipped below 96 per cent, "especially on mild exercise such as walking up the stairs or going for a short walk".
"If it dips at that time, that's a real warning signal," he told the BBC.
He added: "One of the things I would say is, not to be a doctor at home as it were, but if one has one of these machines and one is concerned, to call 111 or your GP practice because certainly the NHS is willing to see people earlier than they are at the moment."
New Zealand to lift lockdown
New Zealanders will be able to go fishing, surfing, hunting and hiking this week for the first time in more than a month as the country begins to ease its way out of a strict lockdown.
Around 400,000 people will return to work after the country shifts its alert level down a notch at midnight on Monday, but shops and restaurants will remain closed as several social restrictions remain in place.
Many businesses, including parliament and the courts, began preparations over the weekend to restart operations this week while maintaining ongoing social distancing rules.
"We must make sure that we do not let the virus run away on us again and cause a new wave of cases and deaths," the prime minister, Jacinda Ardern. "To succeed we need to hunt down the last few cases of the virus."
New Zealand's director-general of health, Ashley Bloomfield, said the low number of new cases gave authorities "confidence that we have achieved our goal of elimination". He said this did not mean there would be no new cases, but said it meant "we know where our cases are coming from".
Govermment's track and trace plans will be 'real logistical challenge'
Professor Peter Horby, chairman of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), said the government's plans to move into tracking and tracing future Covid-19 patients would be a "real logistical challenge".
He told BBC Radio 4's Today programme: "The test and trace capabilities are really going to be critical as we come out of lockdown.
"We will have to be able to test all those people (declaring via apps that they are displaying symptoms) and it is really a matter of scale and speed.
"One issue is how many tests we need, and if we are looking at 1,000 to 5,000 new cases per day of people with symptoms, of which maybe 5-25% may have Covid, then you are talking about 25,000 to 100,000 tests per day.
"It is a real logistical challenge. But there is also the issue of speed as well.
"It is not much use getting the results five days later, you need it quickly so you can take the appropriate action and advise people to stay at home and also their contacts to stay at home to reduce transmission."
UK 'not there yet' when it comes to easing social distancing measures
Health minister Edward Argar said "we're not there yet" when it comes to easing social distancing measures.
He told BBC Breakfast: "I understand the frustrations that people are having with these measures, they are restrictive and they are very difficult."
He said the measures have "made a real difference".
He added: "I've seen a lot of the speculation in the papers and beyond in recent days but the reality is we're not there yet.
"We're not in a place where the science says it is safe to ease the restrictions."
Coronavirus news you may have missed overnight
The global coronavirus pandemic has now infected more than 2.97 million people worldwide and an estimated 205,948 deaths have been recorded.
In the UK, 152,840 people have been confirmed to have caught the disease, while the country’s hospital death toll has reached 20,732.
Here is your morning briefing of everything you may have missed overnight, from Chiara Giordano.
Coronavirus news you may have missed overnight
Covid-19 has now infected more than 2.97 million people worldwide, with more than 200,000 deaths recordedGiving a speech outside Downing Street, Boris Johnson said the UK was beginning to "turn the tide" on the coronavirus.
He described Covid-19 as the "biggest single challenge this country has faced since the war," in his first public statement since he returned to work after being hospitalised with the disease.
Boris Johnson says lockdown cannot yet be eased and now is time of 'maximum risk'
Boris Johnson has said the coronavirus lockdown cannot be eased yetMr Johnson thanked those who had "stepped up" in his absence, including his stand-in Dominic Raab.
He said he had been "away from my desk for much longer than I would've liked".
Addressing the nation he said: "Once again I want to thank you the people of this country for the sheer grit and guts you've shown and are continuing to show.
"Every day I know that this virus brings new sadness and mourning to households across the land."
Mr Johnson continued: "It is still true that this is the biggest single challenge this country has faced since the war and I in no way minimise the continuing problems we face.
"And yet it is also true that we are making progress with fewer hospital admissions, fewer Covid patients in ICU and real signs now that we are passing through the peak.
"And thanks to your forbearance, your good sense your altruism, your spirit of community, thanks to our collective national resolve, we are on the brink of achieving that first clear mission to prevent our National Health Service from being overwhelmed in a way that tragically we have seen elsewhere.
"And that is how and why we are now beginning to turn the tide."
Johnson compares coronavirus to 'unexpected and invisible mugger'
Mr Johnson said: "If this virus were a physical assailant, an unexpected and invisible mugger - which I can tell you from personal experience, it is - then this is the moment when we have begun together to wrestle it to the floor.
"And so it follows that this is the moment of opportunity, this is the moment when we can press home our advantage, it is also the moment of maximum risk.
"I know there will be many people looking at our apparent success, and beginning to wonder whether now is the time to go easy on those social distancing measures."
He said he understood "how hard and stressful it has been to give up, even temporarily, those ancient and basic freedoms".
But he said the potential of a second spike in cases risked "economic disaster".
Mr Johnson added: "And so I know it is tough. And I want to get this economy moving as fast as I can, but I refuse to throw away all the effort and the sacrifice of the British people and to risk a second major outbreak and huge loss of life and the overwhelming of the NHS.
"And I ask you to contain your impatience, because I believe we are coming now to the end of the first phase of this conflict and in spite of all the suffering we have so nearly succeeded.
"We defied so many predictions. We did not run out of ventilators or ICU beds. We did not allow our NHS to collapse, and on the contrary we have so far collectively shielded our NHS so that our incredible doctors and nurses and healthcare staff have been able to shield all of us from an outbreak that would have been far worse and we collectively flattened the peak."
Mr Johnson concluded: "And so when we are sure that this first phase is over and that we are meeting our five tests: deaths falling, NHS protected, rate of infection down, really sorting out the challenges of testing and PPE, avoiding a second peak, then that will be the time to move on to the second phase in which we continue to suppress the disease and keep the reproduction rate - the R rate - down, but begin gradually to refine the economic and social restrictions and one-by-one to fire up the engines of this vast UK economy.
"And in that process difficult judgments will be made and we simply cannot spell out now how fast or slow or even when those changes will be made, though clearly the government will be saying much more about this in the coming days."
Boris Johnson compares coronavirus to 'unexpected and invisible mugger' as he says says too soon to ease lockdown
UK government again runs out of home testing kits after just one hour
The UK government has run out of home testing kits for coronavirus in just over an hour
'Three-month timeline' to develop test for checking if someone has already had virus
Dr Mario Gualano, chief executive of BBI Solutions, said the consortium he is part of, which is looking to develop a test to diagnose whether someone has already had coronavirus, is working to a "three-month timeline" for having it ready for mass production.
It comes after a team at Oxford University, working under the leadership of Professor Sir John Bell, developed an antigen that is being used as "the basis of the test", he said.
Dr Gualano told BBC Radio 4's Today programme: "We believe the antigen is good at picking up convalescent sera, i.e. serum from people that have been identified and are therefore assumed to have some form of immunity.
"It typically takes nine to 12 months to develop a test like this and we are looking at really driving this development in a much shorter timeframe."
Asked for a date when an antibody test could be expected to be widely available, he said: "It is very early days, so it is difficult to put a specific timeline on the availability of the test.
"We are certainly working to a timeline of three months and hoping that we would have developed a test and have something available to go to production at that time."
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