The Prime Minister also declined to rule out bringing in new tougher Covid-19 restrictions before Christmas. 

Answering questions at a vaccination centre this morning, Mr Johnson said that omicron could make up the majority of new Covid cases in London by tomorrow. 

This graph shows the number of cases of omicron we could see by Christmas. Scientists have warned the variant reduces the levels of Covid-fighting antibodies 30-fold, leaving the double vaccinated at far greater risk of catching the virus. 

These charts show how three doses of Pfizer protect the immune system against it. 

The UK Covid alert level has been raised following the rapid increase in omicron cases being recorded. 

Here is what Level 4 means for you and read how the current restrictions compare to February. 

Meanwhile, Telegraph readers have been giving their thoughts on being asked to work from home again from today.

‘No guarantees’ on schools

The inevitable next question from parents is: will the schools stay open? 

Unfortunately, Sajid Javid, the Health Secretary, said he could not rule out that classrooms would not close again due to the pandemic. 

Asked whether this remained a possibility, Mr Javid said “there are no guarantees” as he urged people to get their booster jabs. 

Patrick O’Flynn sets out why closing schools again would be unforgivable. 

Tighter restrictions would also likely see sections of the economy closed, with one top economist warning the UK could take a hit to GDP of almost 6pc if retail and consumer businesses are forced to shut again.

Surviving on tepid wine

The chaos at home appears in contrast with the UK’s looming travel picture, where red list rules could be eased later this week. 

Transport Secretary Grant Shapps has reportedly convinced colleagues to loosen restrictions on travellers. 

A plan is expected to be approved in the coming days and hotel quarantine could be replaced with testing for fully vaccinated travellers.

One British couple detail here their dismal 11-day sentence at a Holiday Inn after returning from red-listed South Africa, being forced to survive off tepid wine and Waitrose deliveries.

Comment and analysis

Around the world: Russia warned on gas pipeline

The Nord Stream 2 gas pipeline will not go ahead if there is Russian “escalation” over Ukraine, Germany has confirmed for the first time. “In the event of further escalation this gas pipeline could not come into service,” Annalena Baerbock, the foreign minister, said. Ms Baerbock’s comments appeared to confirm reports the US has secured a commitment from Germany to abandon the £8bn pipeline if Russia attacks Ukraine. This illustration shows the route of the pipeline.

Monday interview

‘It’s hard to find TV comedy that isn’t trying too hard to be nice’