Allan Monks, an economist at JP Morgan, says the direct impact of the restrictions is likely to be small, but the duration will be crucial. The Government has set out a six-week window, but the pandemic has repeatedly put paid to previous timelines.

“The work from home requirement is probably the most significant, as unlike the others it will prevent some forms of spending from occurring” says Monks.

“Unless the government decides to proceed with greater restrictions, we would not expect any new fiscal measures.”

How Britons respond could prove to be the crucial factor. The restrictions don’t directly block certain forms of activity, as previous versions did. Cinemas, theatre shows and gigs remain legal but unvaccinated people won’t be able to attend, and some may shirk at the requirement to wear masks in more settings.

Fast-moving data suggests omicron has so far had a limited effect on consumer behaviour.

Google Mobility shows a small dip in usage of transport stations since late November, dropping from about 25pc below pre-pandemic levels to 27pc under. Other categories of movement, including to workplaces and retail locations, have barely shifted.

But Consultancy Springboard says this won’t last long. It predicts retail footfall will drop to 50pc below its pre-pandemic levels in central London while restrictions are in place, from around 10pc lower currently, and will be 30pc lower in cities outside the capital.

Lisa Hooker, head of consumer markets at PwC, said a push for early shopping ahead of Christmas may have reduced the blow, however, amid concerns over availability and supply shortages.

“Consumers have been savvy and shopped online early to allow for stock shortages and longer delivery times,” says Hooker.