Video report by ITV News Correspondent Hannah Miller
Boris Johnson will hold a press conference at 6:30pm on Saturday amid growing speculation England could be placed under a national lockdown.
The prime minister will appear alongside chief scientific adviser Sir Patrick Vallance and chief medical officer Professor Chris Whitty at Downing Street, following leaks in Saturday's newspapers over new national restrictions designed to curb the spread of coronavirus.
Everything could be closed except essential shops, courts and educations settings, with the measures remaining in place until December 2, ITV News understands.
Political Editor Robert Peston says the PM will place England into what will effectively be a new 'Tier 4' for a month, with new restrictions set to be enforced from "one second past midnight on Thursday".
Mr Johnson has so far resisted pressure to reintroduce nationwide restrictions, despite calls for a “circuit-breaker” to curb the rise in coronavirus cases.
But new data published on Friday suggested around 570,000 people per week are becoming infected with Covid-19 across England, prompting fresh calls from scientists for tougher restrictions.
The Office for National Statistics (ONS) infection survey found cases “continued to rise steeply” in the week ending October 23, with an estimated 568,100 people in households becoming infected.
Scientific advisers at the top of government believe it is now too late for a two-week national circuit-breaker to have enough of an effect and a longer national lockdown is needed to drive the reproduction number, or R value, of the virus below one.
ITV News Political Correspondent Romilly Weeks explains the options facing England
They are also warning the UK’s second coronavirus wave is on track to surpass the “reasonable worst case scenario” of 85,000 deaths.
All parts of England are on course to eventually end up in Tier 3 restrictions, they believe, while deaths could potentially hit 500 per day within weeks and continue that way for three months.
In a document from the government's Scientific Advisory Group for Emergencies (Sage), dated October 8 and leaked to The Spectator earlier this week, warned a continued rise in hospital admissions means that “if there are no decisive interventions, continued growth would have the potential to overwhelm the NHS, including the continued delivery of non-Covid treatments”.
A separate Scientific Pandemic Influenza Group on Modelling, Operational sub-group (SPI-M-O) consensus statement dated October 14 said “combined estimates from six SPI-M-O models suggest there are between 43,000 and 74,000 new infections per day in England”.
In September, the government’s chief scientific adviser Sir Patrick Vallance warned that without action, the UK could see 50,000 coronavirus cases a day by mid-October and more than 200 daily deaths.
Over the last week, deaths have averaged 230 a day while the latest ONS data suggests more than 50,000 cases a day.
In a tweet, shadow health secretary Jonathan Ashworth called on Mr Johnson to "get a grip of this crisis".
"Boris Johnson needs to show some actual leadership and get a grip of this crisis," Mr Ashworth tweeted.
"He should have followed the advice of scientists and used the school half term for a time limited circuit break to push infections down and save lives."
On Friday evening a number of experts were calling for a lockdown.
Sage member Professor Christina Pagel, from UCL, said another national lockdown is “inevitable”.
"Given that it’s inevitable I think the sooner you do it the quicker it’s over and the more lives you save," she told Sky News.
Professor Jeremy Farrar, a member of the Scientific Advisory Group for Emergencies (Sage), has said: “To bring #COVID19 under control, we have to act now. The virus will not wait for us.”
The infectious disease expert wrote on Twitter: “Nobody ‘wants’ a lockdown, myself very much included. Full & generous support for people & businesses is a crucial part of making it work.
“But we have quickly breached the reasonable worst-case scenario, we are further ahead in this phase of the epidemic than many have assumed.
“The best time to act was a month ago but these are very tough decisions which we would all like to avoid. The second-best time is now.”
Another Sage member and president of the epidemiology and public health section at the Royal Society of Medicine, Professor Gabriel Scally, said on Twitter: “It is possible to be very concerned about the impact of the pandemic on mental health and the treatment of non-Covid conditions, and still believe that stricter measures are the best and most necessary course of action.
“The more the virus spreads the less capacity the NHS has.”
Professor Anthony Gordon, a critical care expert at Imperial College London, warned that if the NHS becomes “overwhelmed” then it will not be able to provide the best care for coronavirus patients.
“We have to stop the spread of the virus because if we don’t we will overwhelm the health service and none of us want that,” he told Today.
On Friday, the government said a further 274 people had died within 28 days of testing positive for Covid-19, while a further 24,405 lab-confirmed cases were recorded in the UK.
The new ONS figures, based on 609,777 swab tests taken whether people have symptoms or not, show the highest rates are in the North West and Yorkshire and the Humber.
Rates also remain high in the North East, but the ONS said these have now levelled off and “there is now a larger gap with the other two northern regions”.
Analysis by the PA news agency of the data shows that the estimated percentage of people in north-east England testing positive went from 0.57% for the period September 12 to 25 to 1.41% for the period of September 26 to October 9.
But the rate of increase appears to be levelling off, with the latest figure being 1.43% for the period October 10 to 23.
In contrast, the North West has jumped from 1.57% for September 26 to October 9 to 2.47% for the period October 10 to 23.
The lowest rates are in the South East, South West and eastern England, while there has been growth in all age groups over the past two weeks.
Sage said on Friday the reproduction number, or R value, of coronavirus transmission for the whole of the UK is between 1.1 and 1.3 – representing the situation over the last few weeks.
Last week, the group said the R number was slightly higher at between 1.2 and 1.4.