Lockdown easing to allow groups of six to meet
The PM warned the country should make only "limited and cautious" progress out of lockdown, which has been in place since 23 March.
The UK government's chief scientific adviser, Sir Patrick Vallance, echoed Mr Johnson's message of caution.
Sir Patrick said the rate of infection was "close to one" - the rate at which the number of new cases can rise rapidly - and that "we are still seeing new infections every day at quite a significant rate".
"That means there is not a lot of room to do things and things need to be done cautiously, step-by-step and monitored and the test and trace system needs to be effective in order to manage that," he said.
His warning came as a
new study by the Office for National Statistics suggested one in 15 people in England (about 7%) have already had the virus.
What are the five tests for easing lockdown?
After Easter, the government set out five conditions for easing lockdown measures safely.
The prime minister has said that - as of 28 May - these are being met sufficiently to slightly ease restrictions in England.
1. Making sure the NHS can cope - Mr Johnson said this test was met because there were only 475 hospital admissions in England on 26 May
2. A 'sustained and consistent' fall in the daily death rate - deaths have been falling since the middle of April, with 377 reported on Thursday, meeting this test, he said
3. Rate of infection decreasing to 'manageable levels' - with an average of 2,312 new cases being confirmed in the last seven days, Mr Johnson said this test was met
4. Ensuring supply of tests and PPE can meet future demand - test capacity was at 161,214 a day and new contracts for protective equipment had been signed, the prime minister said
5. Being confident any changes would not risk a second peak that would overwhelm the NHS - Mr Johnson said the adjustments were "carefully designed" to keep the
R number (the average number of people each infected person passes the disease to) below one
In a separate move on Thursday, the government
told dental practices in England they can reopen from Monday, if they put in place appropriate safety measures.
Nurseries and schools - for Reception, Year 1 and Year 6 classes - in England
will also be able to reopen from next week.
Outdoor markets and car showrooms will also be able to reopen from Monday. They will be followed by non-essential retailers from 15 June if the five tests continue to be met, the PM said.
On Wednesday, Mr Johnson told MPs that he hoped to reduce the length of the two metre social distancing measures "as we make progress in getting the virus down".
The World Health Organization says that a distance of one metre is safe, while other countries suggest 1.5m or 1.8m.
But Prof Whitty said the UK's advice would not be changing, adding that staying a metre away was "somewhere between 10 and 30 times more risky than at two metres".
Meanwhile, a further 377 people have died with coronavirus across all settings in the UK, according to daily figures released on Thursday.
The total number of deaths in and outside of hospitals is now 37,837, the Department of Health said.
I have worked out that the deaths as a percentage of the total deaths from the previous week do appear to be falling in the UK. See below.
1 May 27,500 +40%
8 May 31,241 +14%
15May 33,998 + 9%
22May 36,393 + 7%
28May 37,837 + 5% estimated by 29 May
