Two-week-long ‘circuit breakers’ would see tough restrictions introduced temporarily across the whole country to suppress the virus, before they would be lifted for a time and then re-introduced if necessary.
Measures could include bans on social between households, shutting down hospitality and leisure venues such as bars and restaurants, or restricting their opening hours.
But they are unlikely to lead to schools and offices closing for the time being.
This form of lockdown was first put forward by Singapore Prime Minister Lee Hsien Loong, which he implemented in April.
He closed all workplaces except those deemed essential and place restrictions on public spaces and restaurants.
The idea is seen in England as the ‘last line of defence’, according to Health Secretary Matt Hancock last week, with ‘local action’ preferred.
But north of the border in Scotland, a ‘circuit breaker’ has been seen as a temporary solution.
From October 9, pubs and bars in the central belt were being banned from serving alcohol indoors for 16 days and must shut by 6pm.
In large areas north of the border hospitality venues are being told to close altogether.
However there is a debate about the impact such a move has, with some questioning what happens as soon as the ‘circuit-breaker’ lockdown is ended.
A circuit-breaker was at the top of a shortlist of coronavirus interventions recommended to the Government by expert advisers last month.
A Sage document, dated September 21 and released just hours after the Prime Minister announced his three-tier system of alert levels for England yesterday, said a package of interventions will be needed to reverse the exponential rise in cases.
Top of the list is a circuit-breaker, a short period of lockdown, ‘to return incidence to low levels’, followed by advice to work from home for all those that can.
Attendees of the September 21 meeting, held via Zoom, included the Government’s chief scientific adviser Sir Patrick Vallance and chief medical officer Professor Chris Whitty.
The document says both local and national measures are needed, adding: ‘Measures should not be applied in too specific a geographical area.’
A separate Sage document, also dated September 21, looking at the effectiveness and harms of non-pharmaceutical interventions, said a circuit-breaker reintroduced for two to three weeks should act to reduce R below one.
‘Over a fortnight’s ‘break’, two weeks of growth could be exchanged for two weeks of decay in transmission, assuming good adherence to measures, and no additional increase in contacts before of after the break.
‘If this were as strict and well-adhered to as the restrictions in late May, this could put the epidemic back by approximately 28 days or more.
‘The amount of ‘time gained’ is highly dependent on how quickly the epidemic is growing – the faster the growth or stricter the measures introduced, the more time gained.
‘If regulations and behaviour then returned to pre-circuit break levels, there would be a return to exponential growth, but from a significantly lower level than would have been the case without the break.
‘The deleterious impact would be maximised if they coincided with school holidays.
‘Multiple circuit-breaks might be necessary to maintain low levels of incidence,’ the document said.
On Monday evening, Sage scientist Professor Calum Semple warned the new restrictions announced by the PM had come too late and a ‘circuit-breaker’ could be needed within weeks.
Asked if the level of response announced for London is sufficient for the threat, the University of Liverpool academic told BBC Radio 4’s PM: ‘I’m going to be difficult and say no, I think we’re a little late to react.’
He said there is a three-to-four-week delay before interventions see benefits in hospitals.
‘I and other people who were advocating for quite stringent severe local interventions where necessary three to four weeks ago, our fear is now that we’re in another place now,’ he said.
‘And that we’re going to need a much firmer intervention perhaps, the so-called circuit-breaker, in the matter of weeks.
‘The outbreak is a bit like a super-tanker, you put the brakes on but it takes a long time before you see the effect.’
Communities Secretary Robert Jenrick today said the Government had taken ‘robust action’ despite being accused of ignoring its own scientists over a ‘circuit-breaker’ lockdown for England.
Mr Jenrick said this had included introducing the rule of six and 10pm curfews for pubs and restaurants but that the Government had also taken a ‘balanced ‘ approach to the situation.
Mr Jenrick told BBC Breakfast: ‘We listened to that advice as we always do and we did take action but these are balanced judgments.
‘We also have to balance that up against the effect on the economy, people’s jobs and livelihoods, on education which we have made a priority and all the other unintended consequences of taking action, whether that is on people’s mental health, on other illnesses and elective surgery that might be delayed or cancelled as a result of that.
‘We took a balanced view as to what was required at that moment and that’s the way we will continue to behave.’
Despite it being the reintroduction of restrictions on freedom, nearly two-thirds of the public said they would back a Scottish-style ‘circuit breaker’ lockdown.
An exclusive poll for MailOnline last week found strong support for a ‘short sharp shock’ of tough restrictions across the country in a bid to break transmission chains.
The Redfield & Wilton poll found 63 per cent would back a temporary crackdown being introduced across the UK – including 33 per cent who said they were strongly supportive.
By contrast, just 13 per cent of the 3,000 polled said they would be against the move.