The prime minister has said 405,000 people have volunteered for the NHS through the coronavirus crisis.
The announcement comes after the Government asked 250,000 people to come forward to help the health service as it faces its biggest challenge since its inception.
Mr Johnson, speaking at the daily press conference inside Number 10, said he wanted to offer a “special thank you to everyone who has now volunteered to help the NHS”.
“When we launched the appeal last night, we hoped to get 250,000 volunteers over a few days.
“But I can tell you that in just 24 hours, 405,000 people have responded to the call.”
Coronavirus testing kits are coming, despite 'global bottleneck'
The UK’s chief medical officer Professor Chris Whitty said there was a “global bottleneck” on buying more testing kits.
Speaking at the press conference, he said it was the Government’s aim to be able to buy tests that would allow NHS workers to go back to work if they test negative for coronavirus.
“This is a global problem – every country wants this new test for a disease that wasn’t being tested for anywhere three months ago,” he said.
“Everybody wants it so there is a global shortage and that’s a bottleneck for us.
“The next priority is to get critical workers back to work or to say to them, ‘You have got it’. We definitely would like that.”
Authorities have said more than 8,000 people have contracted the deadly virus in the UK so far.
The youngest victim has been named by her family as a 21-year-old from High Wycombe in Buckinghamshire.
Chloe Middleton had no pre-existing health conditions, her family said in a statement released on social media.
The conference comes after the Government introduced a lockdown on the United Kingdom, seeing the majority of shops and businesses closed, bar those deemed essential.
Millions of Britons have been told to stay at home, with police enforcing the rules on those that defy the orders.
It is anticipated the rules will be reviewed in three weeks, at which point officials will make a decision to end the measures or extend them further.
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