The number of people who have volunteered to help the NHS in its fight against coronavirus has passed half a million, double the government's recruitment target.
Speaking at his daily news conference, PM Boris Johnson said all 504,303 could now play an "absolutely crucial" role.
The helpers are needed for delivering food and medicines, driving patients to appointments and phoning the isolated.
The scheme is one of a number aimed at relieving pressure on the NHS.
Mr Johnson said he a wanted to offer "special thank you to everyone who has now volunteered to help the NHS".
He added: "And to all of you, and all the former NHS staff who are coming back into the service, I say thank you on behalf of the entire country."
About 11,000 former medics have also agreed to return to the health service and more than 24,000 final year student nurses and medics will join them.
Stephen Powis, NHS England medical director, said there had been "outbreaks of altruism" and he was "bowled over" by the medics returning to the front line and the response from volunteers.
This comes as it was confirmed Prince Charles, the 71-year-old heir to the throne, tested positive for coronavirus after displaying mild symptoms.
He is now self-isolating at home in Scotland with the Duchess of Cornwall, who tested negative.
A Clarence House spokesman said it was not possible to know who he had caught it from due to a "high number of engagements" in recent weeks.
Figures released from NHS England show there were 28 deaths over the latest recorded 24-hour period, bringing the death toll in England to 414.
There have also been 22 deaths so far in Scotland, 22 in Wales and seven in Northern Ireland, according to the latest available figures.
The government scheme to recruit 250,000 helpers - who must be over 18 and in good health - went live on Tuesday.
By Wednesday morning, they had exceeded their target, after many thousands signed up to Good Sam, the group coordinating the response.
The help is being targeted at the 1.5 million people with underlying health conditions who have been asked to shield themselves from the virus by staying at home for 12 weeks.
Housing Secretary Robert Jenrick tweeted a photo of what he said was the first box of food and supplies ready to be sent out.
💥The first #Shield food and supplies box - ready for despatch to one of the 1.5m people we are shielding.💥— Robert Jenrick (@RobertJenrick) March 25, 2020
Thank you to everyone working round the clock on this national endeavour. An amazing effort! #StayHomeSaveLives pic.twitter.com/Edi1DpMxRH
There are now calls to replicate the volunteering scheme - which is currently only for those in England - in Wales.
Meanwhile, Parliament has shut down until 21 April at the earliest, after sweeping emergency powers to tackle the coronavirus crisis were passed.
Health Secretary Matt Hancock told MPs the emergency legislation will allow "extraordinary measures" never seen in peacetime in the UK.
'I just want to help': Meet the volunteers
Technology expert Alex Hamilton, from Northampton, was among the first to sign up.
"I'm working from home but it's quiet. I'm doing a lot of gardening and this is an opportunity to do something to help - I've volunteered to do anything necessary."
His wife has a low immune system after having breast cancer twice and says she has concerns "about what I could be bringing back".
"But I want to do good," he said.
University tutor Robert Howarth, 23, from Blackburn, has also signed up. "I just want to help," he says.
He is currently working remotely and part-time, which he says gives him the chance to do more.
"I've signed up for two roles out of the four on offer - to be a befriender helping people in self-isolation and delivering vital products."
Actress Claudia Grant is another to have signed up. With much of her industry having shutdown, she says she has time to help.
"I hate to think of anyone struggling and I know the NHS is going to be stretched - I just want to do anything I can to help."
On Tuesday, it was also announced that the NHS will treat coronavirus patients in a makeshift field hospital in the ExCeL Centre in east London.
There has been widespread concern and anger at the shortages of personal protective equipment for doctors and nurses.
At Prime Minister's Questions, Labour leader Jeremy Corbyn said the Healthcare Supply Association has been forced to use Twitter to ask DIY shops to donate equipment to NHS staff.
The prime minister said he has been "assured" stocks were on the way, saying the army had distributed 7.5 million pieces of equipment in the past 24 hours.
The government is also facing growing pressure to stop non-essential construction work to help tackle the spread of coronavirus in the UK.
On Tuesday, Mr Hancock said those who cannot do their jobs from home should go to work to "keep the country running" and construction work could continue so long as people were 2m (6.5ft) apart.
But critics said public health should be prioritised over the economy.
Some builders and construction workers have said they feel "angry and unprotected" going to work, while others are under pressure from employers to go in.
Mr Johnson has so far resisted pressure from politicians, unions and workers themselves to halt construction work.
The confusion over who should and should not be travelling for work came after government guidance announced by Mr Johnson on Monday curtailed many freedoms on life in the UK.
The prime minister said people should only leave their home to shop for basic goods, to fulfil medical or care needs, to exercise, and to travel to and from work - but only where "absolutely necessary".
Since Tuesday evening, hundreds of British Transport Police have been deployed onto the rail network to tell travellers that only those making essential journeys for work should be using tubes and trains.
The prime minister confirmed the government was considering asking black taxi drivers to take NHS workers to work so that they can avoid public transport.
Public services are coming under increasing strain - London Ambulance Service said it was receiving 8,000 calls a day - up 3,000 on a "very busy" day before the coronavirus pandemic.
Meanwhile, calls to the 111 service have increased by up to 400%.
The Department for Work and Pensions processed almost half a million benefit claims over nine days.
Meanwhile, the government is considering the early release of some prisoners in England and Wales to relieve pressure.
Justice Secretary Robert Buckland said the virus posed an "acute" risk in prisons, many of which were overcrowded and faced staff shortages as officers self-isolated.
Some 19 inmates have now tested positive for coronavirus in 10 different prisons.
Elsewhere, the government remains under pressure to provide financial support for self-employed workers who face a loss of income if forced to stop working due to sickness or quarantine.
Mr Johnson said a package of support for those workers would be announced on Thursday.
In other key developments:
- Dyson has had hundreds of engineers working round the clock to make 10,000 ventilators, after the government placed an order
- British diplomat Steven Dick, 37, has died in Hungary after contracting coronavirus
- BBC Director General Tony Hall has "paused" plans to cut 450 news jobs, saying it would be inappropriate while BBC News was so stretched
- UK vehicle owners will be granted a six-month exemption from MoT testing
- Three immigration removal centres in the UK are housing people with symptoms of the virus
- A quarter of the world's population is now living under some form of lockdown
- The death toll in Spain has overtaken China, rising by 738 to 3,434
- People in India have begun panic-buying as the entire population of 1.3bn enters "total lockdown"
- US lawmakers have agreed a $2 trillion stimulus package
- Global cases of the virus have exceeded 400,000 with deaths approaching 20,000