When the last lockdown ended, England returned to tiered arrangements which restricted the activities permitted in an area depending on the state of the virus.
Mr Johnson told reporters in Batley, West Yorkshire: “It may be that a national approach, going down the tiers in a national way, might be better this time round, given that the disease is behaving much more nationally.
“If you look at the way the new variant has taken off across the country, it’s a pretty national phenomenon.
“The charts I see, we’re all sort of moving pretty much in the same sort of way, I mean there are a few discrepancies, a few differences, so it may be that we will go for a national approach but there may be an advantage still in some regional differentiation as well. I’m keeping an open mind on that.”
Facing opposition from Conservative MPs sceptical of lockdowns, Mr Johnson rejected Sage’s recommendation and pushed on with the tiered system of restrictions.
But as cases began to spiral out of control, more than a month later Mr Johnson imposed a four-week lockdown lasting until December 2.
England emerged into a new four-tier system, but it ultimately saw most of the nation placed into the highest level of restrictions before a national lockdown was imposed on January 4, as a new highly-infectious strain emerged from Kent.
On January 27, Communities Secretary Robert Jenrick said “it’s sensible that we target restrictions on those places where the virus is most prevalent”.
The latest R estimate for England is between 0.7 and 1.0 and remains broadly similar to last week’s figures.
Health officials said 11 people had been identified over the last five or six days who have tested positive for the variant, but who have no links to travel.
Experts from Public Health England (PHE), who have been sequencing around 5% to 10% of all positive cases looking for variants, are now hoping to break any chains of transmission. All but two areas involved single cases of the variant.
Mobile testing units and some home testing kits are being sent into the affected areas of London, the West Midlands, East of England, South East and the North West.
The areas are: Hanwell, west London; Tottenham, north London; Mitcham, south London; Walsall in the West Midlands; Broxbourne, Hertfordshire; Maidstone, Kent; Woking, Surrey; and Southport, Merseyside.