Boris Johnson is set to hold a Downing Street press conference on Saturday evening amid reports of a second nationwide lockdown.
The prime minister is expected to be joined by Professor Chris Whitty and Sir Patrick Vallance during the press conference, following a meeting of his cabinet earlier in the afternoon.
It emerged on Friday evening via The Times and the Daily Mail that ministers were planning to announce a second lockdown for the whole of England, starting on Wednesday and ending on December 1.
The government has not yet made any official announcement and details are scarce, but it is anticipated that everything will close with the exception of schools and essential shops.
A leak inquiry has been launched in Whitehall after the plans were allegedly briefed to journalists, with reports that ministers planned to keep the announcement secret until a press conference with the PM on Monday.
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.
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.
Government scientists are also confident that more than 50,000 new cases of coronavirus are now occurring every day in England.
Over the last week, deaths have averaged 230 a day while the latest ONS data suggests more than 50,000 cases a day.
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.