Boris Johnson has been moved to intensive care in hospital, suffering from persistent coronavirus symptoms.
While Mr Johnson will remain prime minister, foreign secretary Dominic Raab, who insisted hours earlier that Mr Johnson would remain at the helm, will take charge for the time being.
After Mr Johnson was admitted for tests and observation on Sunday, his doctors advised that he be taken to intensive care on Monday evening.
He is understood to be conscious and was moved to intensive care “as a precaution should he require ventilation to aid his recovery”.
Downing Street, which had previously described Mr Johnson’s symptoms as “mild”, switched to describing them as “persistent”.
The Queen has been kept informed by Downing Street about Boris Johnson’s condition, Buckingham Palace has said.
Mr Johnson’s fiancee, Carrie Symonds, who is pregnant, has also been suffering Covid-19 symptoms.
Please allow a moment for the liveblog to load
Boris Johnson spends night in hospital
Boris Johnson remained in hospital overnight after suffering persistent coronavirus symptoms - although Downing Street said he remained in charge of the government.
"The PM is still at hospital," a government source told Reuters. "He spent the night in hospital."
Mr Johnson, who had been isolating in Downing Street after testing positive for the virus last month, was taken to hospital on last night because he still had a high temperature and his doctors felt he needed additional tests.
"On the advice of his doctor, the prime minister has tonight been admitted to hospital for tests," his Downing Street office said in a statement on Sunday.
Japan likely to declare state of emergency tomorrow
Japan will declare a state of emergency as early as tomorrow in a bid to stop the virus - according to national media - with the government preparing a stimulus package to soften the blow on an economy already struggling to avoid a recession.
More than 3,500 people have tested positive for the coronavirus in Japan and 85 have died, with numbers rising with particularly in Tokyo, which has more than 1,000 cases.
Prime Minister Shinzo Abe was likely to announce his plan for the emergency later on Monday, the Yomiuri newspaper reported, while Kyodo news agency said new measures would likely come into force on Wednesday.
The measure, which is expected to impact Tokyo and its neighbouring prefectures, will likely full short of a total lock down as seen elsewhere int he world.
US officials have continued to urge optimism in the fight against coronavirus despite grave warnings from experts including the nation's surgeon general.
"This is going to be our Pearl Harbour moment, our 9/11 moment, only it's not going to be localised. It's going to be happening all over the country. And I want America to understand that."
New Zealand sees promising signs - but restrictions will remain
New Zealand will maintain its stringent level four coronavirus restrictions despite some early signs the spread of the illness has been stabilising.
The country's 67 new infections were the lowest in five days, taking its tally to just over 1,100. New Zealand has reported one death.
Level-four curbs allow people to take walks or go to supermarkets for essentials, but they are required to stay 2 metres apart.
"Our actions for the remainder of the period in level four will be about doubling down to ensure the gains made in the first half are not squandered in the second," PM Jacinda Ardern told reporters in Wellington.
Boris Johnson is "still very much in charge of the Government" despite spending a night in hospital with the coronavirus, Housing and Communities Secretary Robert Jenrick has said.
He told BBC Breakfast: "He spent the night in hospital and of course we all wish him well and we hope that as a result of these tests he will be able to come back to Downing Street as soon as possible.
He added that lockdown measures could be gradually eased "in the weeks to come", while urging the nation is currently heading into the most difficult weeks of the outbreak.
In case you missed it on Sunday evening - Scotland‘s chief medical officer has resigned from the government after breaking coronavirus lockdown rules by visiting her second home.
Dr Catherine Calderwood agreed to step down just hours after “unreservedly” apologising for the trip to Fife and withdrawing from giving public briefings.
More below:

Scotland's chief medical officer resigns after breaking lockdown rules
‘I am deeply sorry for my actions and the mistakes I have made,’ says Catherine CalderwoodKike Mateu covers Valencia - and Keen followers of Spanish football may recognise him as one of the contributors to El Chiringuito de Jugones, a lively late night debate show which discusses La Liga’s latest gossip and talking points.

Did a Champions League match spark Italy's coronavirus crisis?
The public health disaster that was Atalanta’s last-16 first leg against Valencia could not have been avoided, according to those who were there, but did we learn from its lessons?When it comes to the news, last night was - and I'm using the technical journalistic term here - a bit of a busy one.

Coronavirus news you might have missed overnight
Prime minister will continue to lead government’s efforts to tackle Covid-19 outbreakRussia's coronavirus case tally has risen to 6,343 in the past 24 hours, a record daily increase of 954, the country's crisis response centre has said.
Cases have been recorded widely, but Moscow remains the epicentre of the outbreak with 591 new cases.
The former head of the civil service Lord Kerslake said it would be "sensible" for Boris Johnson to "step back" if he is not well enough to carry out his role for now.
He told BBC Radio 4's Today programme: "If he's not well enough it would be sensible to step back and let others take on the role."
He added: "I think in the end if he's not well, he will have to reflect on this because the job's tough at the best of times and it's doubly tough now."
Ministers have assured the PM is continuing his work despite his condition.
There has been a 25 per cent surge in calls to the National Domestic Abuse helpline in a five-day period during the coronavirus lockdown, the charity Refuge said.
In the week starting on March 30, from Monday to Friday, the helpline saw a significant daily rise in calls and contacts.
There was also an increase of around 150 per cent in visits to nationaldahelpline.org.uk compared with the last week in February.
Refuge chief executive Sandra Horley said: "1.6 million women experienced domestic abuse last year, and self-isolation has the potential to aggravate pre-existing abusive behaviours by perpetrators.
"While in lockdown or self-isolation, women and children are likely to be spending concentrated periods of time with perpetrators, potentially escalating the threat of domestic abuse and further restricting their freedom.
"Domestic abuse isn't always physical - it's a pattern of controlling, threatening and coercive behaviour, which can also be emotional, economic, psychological or sexual.
"Abuse is a choice a perpetrator makes, and isolation is already used by many perpetrators as a tool of control."
Former prime minister Tony Blair said Boris Johnson's hospital situation is "hellish".
He told Today: "I have every sympathy and solidarity with him. I know it must be a hellish situation to be in."
"He knows the state of his own condition and he will be judging it carefully himself, I'm sure."
Eddie Large's widow, Patsy McGinnis, has said it has been heartbreaking not being able to see the comedian following his death from coronavirus.
Appearing on Good Morning Britain, she said of her last conversation with him: "I wanted to talk to him longer but he said 'Darling, I am going to have to go now'.
"I said 'Don't worry, love - I will speak to you in the morning' but that wasn't to be as in the early hours of the morning - at about four o'clock - they rang to say he had passed away and we couldn't be with him.
"I never thought it would end like this, I really didn't, and I know a lot of families are going through the same thing. It is such a terrible time.
"But I wish we could have been with him and even when we... Trying to get a funeral together, we still won't be able to see him. It's heartbreaking."
The infographic below, produced for the Independent by statistics agency Statista, shows the capital still vastly outstrips the rest of the country for the number of cases, followed by the midlands which last week was described as an increasing concern by the deputy chief medical officer Dr Jenny Harries.
Poland is still at the beginning of its fight with the coronavirus, with the peak of infections expected in May and June, Prime Minister Mateusz Morawiecki has said.
Speaking to the lower house of parliament, Mr Morawiecki said the nation has some shortages of medical equipment. It plans to increase within days the number of daily coronavirus tests to 8,000-9,000 from the current 6,000-7,000, he said.
Poland has reported 4,201 coronavirus cases, including 98 deaths.
Tens of thousands of Chinese students complete degrees in Britain every year, but fears for their safety amid the coronavirus pandemic have seen hundreds trying to get home.

‘I feel safer in China’: The international students fleeing the UK
Tens of thousands of Chinese students complete degrees in Britain every year, but fears for their safety amid the coronavirus pandemic have seen hundreds trying to get home, reports Emily GoddardIsraelis who have beards for religious reasons will get the option of custom-made face masks to protect them from the coronavirus rather than being told to shave, a government official said.
Many of the country's Jews and Muslims, and some Christian clergymen, wear beards as a mark of faith, and a government order to cover mouths and faces in public raised questions as to how facial hair would be accommodated.
Health Ministry deputy director-general Itamar Grotto said masks would be adapted accordingly.
"We are creating an industrial certification for masks, which means that in a few days there will really be masks of different sizes," he told Army Radio.
"...(So) those with beards will be able to use the appropriate masks."
In 'things you would hope don't need to be stated but somehow still do' news, scientists have poured scorn on a viral conspiracy theory that suggests there is a link between 5G networks and the Covid-19 outbreak.
In recent days, celebrities and numerous popular posts have suggested the coronavirus outbreak is either being caused or exacerbated by the rollout of 5G. As a result service providers have reported a number of masts being set alight in recent days.
However beyond it being improbable, such a situation is also impossible.
"There is no scientifically credible evidence to link the introduction of 5G masts with the COVID-19 outbreak," said Brendan Wren, professor of microbial pathogenesis at the London School of Hygiene and Tropical Medicine. "This would be both a physical and biological impossibility.”
More below:

5G-coronavirus conspiracy theory is 'complete rubbish', say scientists
Expert says any link would be 'both a physical and biological impossibility'In aiming to frame why Liverpool’s decision to turn to the government’s Coronavirus Job Retention Scheme rankled so much, a supporter provided the perfect analogy: “It’s like going to the foodbank when you can still comfortably afford to go the supermarket and buy meals.”
Here is more on LFC's decision to furlough workers, despite being one of the world's richest football clubs, while others like Man Utd and Man City promise not to.
