Boris Johnson has sought to raise hopes of people being able to do their Christmas shopping in person throughout much of December.
But the Prime Minister warned this would depend on the second lockdown proving a “success” in reducing the Covid-19 infection rate.
New lockdown rules for England will come into force from Thursday until December 2, and clothes shops, electronic stores and other non-essential retail will close.
The restrictions are expected to offer a further boost to online retailers such as Amazon, and deal another blow to high streets.
He earlier said the intention over the next four weeks is to halve the number of infections.
Mr Johnson said: “The objective is to get the disease to stop doubling, the infection rate to stop doubling and start halving.
“To do that you need to get the R down below one.
“It’s currently estimated to be between 1.1 and 1.3 – I think ONS (Office for National Statistics) said recently it was 1.6 – but it has been coming down.
“Our intention is to use this period to get it below 1 and get that infection rate halving, not doubling.”