Boris Johnson on Monday night announced the end of Covid restrictions and said that if Britain did not seize freedom now then a return to normality could be a long way away.
The Prime Minister announced that laws enforcing face masks and social distancing would be scrapped on July 19, meaning pubs and theatres can operate without restrictions.
He also said the work from home mandate would end and school bubbles would be axed later this month.
Later this week, the Government is also expected to announce the end of self-isolation for fully vaccinated arrivals from amber list countries.
Mr Johnson announced his intention for a full reopening on July 19 despite acknowledging that there could be 50,000 new cases detected daily by then, saying we must "learn to live with this virus".
He told a televised Downing Street press conference: "If we can’t reopen our society in the next few weeks, when we will be helped by the arrival of summer and by the school holidays, then we must ask ourselves ‘when will we be able to return to normal?’
"To those who say we should delay again – the alternative to that is to open up in winter when the virus will have an advantage, or not at all this year."
Mr Johnson’s announcement included the scrapping of the "rule of six", which curbs the number of people allowed to meet indoors, and the 30-person limit on outdoor gatherings.
The cap on named visitors to care homes will be removed, alongside the requirement for people to remain at "one metre plus" from others outside their household or bubble. Rules forcing double-vaccinated people to isolate after coming into contact with a confirmed Covid case are also set to end.
The decision to scrap the legal enforcement of face masks prompted airlines Ryanair and easyJet to announce that they would still require passengers to wear them.
Mr Johnson said government guidance would be put in place suggesting that people wear masks in crowded places such as on public transport, and indicated that businesses including shops and pubs would be allowed to insist upon face coverings should they choose to do so.
But he warned that the nation was "very far from the end of dealing with this virus" and said it was not a moment to "get demob happy".
He said the Government must "balance the risk" of illness from the virus with the harmful impact of continuing restrictions on the population, including the toll on lives, livelihoods and physical and mental health.
Sir Patrick Vallance, the Chief Scientific Adviser, warned that the country was "in the face of an increasing epidemic at the moment and therefore we need to behave accordingly in terms of trying to limit transmission".
It will be formally confirmed next Monday whether the final step of the roadmap out of restrictions will go ahead a week later, but Mr Johnson signalled that confidence levels were high.
The latest data showed that 27,334 new Covid cases were recorded on Monday, while a further nine people had died within 28 days of a positive test. So far, more than 45.4 million people have received the first dose of a Covid vaccine, up 77,222 on the previous day, while 33.7 million have been given both doses – a rise of 111,410.
The gap between vaccine doses for under-40s will be reduced from 12 weeks to eight, meaning all adults will have the opportunity to be double-jabbed by mid-September.
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Mr Johnson also confirmed that proposals for domestic Covid passports had been shelved for the time being but will remain under review. Firms will be able to voluntarily use the system.
Pubs are among the businesses set to see the biggest benefit from the announcement, which heralds the return of drinkers ordering at the bar as the requirement for table service ends, with customers being able to sit at tables of more than six.
The intervention was also welcome news for theatres, sports stadia and event venues which can return to full capacity, as well as festivals. The forced closure of nightclubs will end. The removal of restrictions will also boost weddings, with hymn singing and dancing to be allowed.
Legal requirements to wear face coverings will be lifted, although guidance will suggest people might choose to do so in "enclosed and crowded places". Mr Johnson confirmed that he would wear one in certain settings.
Prof Chris Whitty, the Chief Medical Officer for England, said he would put on a face covering if in a crowded space, if asked to by a competent authority, or if the absence of a mask made anyone else uncomfortable as a "point of common courtesy".
Sajid Javid, the Health Secretary, told the Commons on Monday that the lifting of the measures at step four would be the "biggest step of all, a restoration of so many of the freedoms that make this country great".
However, fears persist among lockdown-sceptic Tory MPs in the Covid Recovery Group that there could yet be a winter lockdown and the introduction of domestic Covid passports.
Newly released papers from the Scientific Advisory Group for Emergencies say "stronger restrictions" may be required in the winter despite Mr Johnson’s pledge that the changes on July 19 would be "irreversible". One undated paper warns that "it is highly likely that transmission will increase in autumn and winter”.
"The healthcare burden of other infections through the year is also an important consideration," the paper says, adding: "This may mean stronger measures may be desirable for autumn and winter."
Asked about his previous insistence that unlocking would be irreversible, Mr Johnson said: "Obviously if we do find another variant that doesn’t respond to the vaccines, if – heaven forbid – some really awful new bug should appear, then clearly we will have to take whatever steps we need to do to protect the public."
Mark Harper, the chairman of the Covid Recovery Group, warned: "The Prime Minister has confirmed that there will be contingency measures in place for winter, and even if they’re not legal restrictions, they will have that effect on business." He demanded ministers urgently publish the details of these measures so MPs could scrutinise them.
Sir Keir Starmer, the Labour leader, accused Mr Johnson of being "reckless" by planning to scrap all legal Covid restrictions at once and said the present face mask rules should remain in place.
"Lifting all protections in one go when the infection rate is going up is reckless. A balanced approach, a proper plan, would say keep key protections," he said. "One of them would be masks in enclosed places and on public transport – that’s a common sense position."