How certain is the June 21 reopening? ITV News Political Correspondent Carl Dinnen takes a look.
Downing Street has indicated that Boris Johnson still sees nothing in the data to suggest the plan to end all legal lockdown restrictions on June 21 will need to be delayed, amid warnings from scientists about further unlocking.
Asked about the Prime Minister’s plans, a Number 10 spokesman pointed to Mr Johnson's comments on Thursday when he said "I don't see anything currently in the data" to divert from the June 21 target for the next stage of exiting lockdown.
The spokesman added: “The Prime Minister has said on a number of occasions that we haven’t seen anything in the data but we will continue to look at the data, we will continue to look at the latest scientific evidence as we move through June towards June 21.”
It comes after a leading scientific advisor said the June 21 lifting of Covid-19 restrictions should be delayed by "a few weeks", warning that the ability of coronavirus to adapt in the face of vaccines has still left the UK in a vulnerable position.
Professor Ravi Gupta, a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), said the UK’s pandemic picture had changed since its road map to recovery was drawn up, chiefly through the emergence of the Indian B1617.2 strain of the virus.
He also warned the increased socialisation following last month’s easing of restrictions could lead to “quite a lot” of hospital admissions, and said while Britain had performed “amazingly well” in its vaccination programme, it was still too early “to put the vaccine straight up against the virus”.
Professor Adam Finn, who also advises the government, said opening too early could lead to the damaging reintroduction of restrictions in the future.
He told BBC Radio 4's Today programme: "There's vulnerability across the country. The idea that somehow the job is done, is wrong.
"We've still got a lot of people out there who've neither had this virus... nor yet been immunised, and that's why we're in a vulnerable position right now."
Professor Finn added "a more infectious virus, which is what it looks like we've got, will reach people who are vulnerable - those who did not make a good response to the vaccine, those who have not yet had their doses - and that will be a problem for everyone because in the end it will be worse economically as well as for public health if we end up having to shut down again."
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However, Robert Dingwall, professor of sociology at Nottingham Trent University, criticised those who were calling for a delay to the June 21 easing and said that it was important to press ahead with the reopening."
He told Times Radio: "I personally, I don't see any case for delay... from a societal point of view, I think it's really important that we go ahead on June 21, and I've not really seen anything in the data that would lead me to doubt that as a proposition on the evidence to date."
Professor Dingwall added: "I think we need to recognise the way in which levels of fear and anxiety in the population have been amplified over the last 15 months or so.
"We've got to look at the collateral damage in terms of untreated cancers, untreated heart conditions, all of the other things that people suffer from.
"We've got to think about the impact of economic damage that would be caused by further periods of delay and uncertainty.
"What we see at the moment I think is really a preview of what it means to live with Covid as an endemic infection - these waves will come, they will pass through; there will be high levels of mild infections in the community for periods of time, a handful of people may be seriously ill, even fewer may die.
"But that's what happens with respiratory viruses, and we've lived with 30-odd respiratory viruses for since forever."
How long would a delay have to be to limit the spread of the virus?
Professor Gupta told ITV’s Good Morning Britain that moving back the June 21 target date could have a significant impact on the fight against the pandemic, adding it should be made clear to the public this would be a temporary measure based on recent developments.
Asked whether a three-week delay to the June 21 target would be sufficient while Britons were being vaccinated at a rate of four million per week, Professor Gupta said: “Even a month delay could have a big impact on the eventual outcome of this.
“As long as it’s clear to people this is not an unlimited extension of the lockdown but actually just a reassessment, that would be realistic.
“Because we didn’t plan for the 617.2 variant when the initial road map was made, and actually things have gone really well except for the fact that we have this new variant to complicate things.
“We must remember this is a virus that does adapt, and faced with vaccines it will eventually start to make mutations to avoid them even further, and then we could be in an even more precarious situation after that.”
Prof Gupta said the UK was in “a really good position” in regard to its vaccination programme but caution remained crucial.
“The key thing here is that we’re almost there,” he said.
“The problem is we don’t want to put the vaccine straight up against the virus at a time when the vaccine coverage isn’t quite high enough; it’s not in young people, it’s not in schoolchildren, and that’s where the virus may potentially start circulating.
“We still have a lot of vulnerable people in the community who haven’t responded to the vaccine.”
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In Scotland, First Minister Nicola Sturgeon will confirm "whether and to what extent" plans to further ease coronavirus restrictions can take place on June 7, amid extra controls in Glasgow to deal with rising cases.
The race to vaccinate the UK gathered pace on Monday after a major walk-in vaccination centre at Twickenham Stadium opened up the jab offer to anyone aged over 18 in order not to waste doses. Around 11,000 jabs were given.
Currently, only those aged over 30 in England are being invited to book their first vaccine.
The call led to lengthy queues in south-west London as thousands of young people lined up for a jab, adding to the 39.3 million people in the UK who have been given a first dose and a further 25.5 million who have had both.
One further death was reported within 28 days of a positive coronavirus test, according to government data.
It comes as the EU's ambassador to the UK has raised hopes that those wanting to holiday in Europe later this summer will find the process easier.
Joao Vale de Almeida told BBC Radio 4's Today programme: "I hope many, many British citizens will come to our countries and I hope many EU citizens will visit the UK."
He said the bloc was hoping a digital Covid certificate would pave the way for greater ability to travel.
"We're hopeful that some time later in the summer, around July, we could be in a situation where travel and tourism will be made a lot easier," he added.
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