The Prime Minister said England will move to Plan B measures in a bid to curb the virus’ spread this winter

Boris Johnson has told people to work from home from Monday as he announced strict new ‘Plan B’ Covid curbs amid fears over the Omicron variant and rising case rates.

Speaking at a Downing Street press conference, the Prime Minister the doubling time of the new strain could be “between two and three days”.

Covid vaccine passports would be made mandatory for nightclubs and large events, and rules on face masks would be “further extended” from Friday, to “most public indoor venues” including theatres and cinemas.

“We will reintroduce the guidance to work from home,” he said. “Employers should use the rest of the week to discuss working arrangements with their employees but from Monday you should work from home if you can.

“Go to work if you must but work from home if you can.

“I know this will be hard for many people but by reducing your contacts in the workplace, you will help slow transmission.”

Meanwhile in the Commons, Health Secretary Sajid Javid told MPs there are 568 confirmed cases of the Omicron variant but the estimated current number is “probably closer to 10,000”.

He said Omicron is “more transmissible than the Delta variant”, adding: “This has made the virus an even more formidable foe.”

The Prime Minister told a press briefing in Downing Street there would be exemptions on mask-wearing “where it is not practical, such as when eating, drinking, exercising or singing”.

The press conference was shown graphs which demonstrated the alarming spread of the new strain in South Africa.

It came as the Scientific Advisory Group for Emergencies (Sage) panel suggested at least 1,000 people a day may need hospital treatment for Omicron by the end of the year without restrictions.

Leaked minutes of their meeting held on Tuesday had said the Government should “urgently” consider the need for measures to reduce transmission of the virus and protect the NHS from “unsustainable pressure”.

The peak of the Omicron wave is “highly likely to be higher” than 1,000 to 2,000 variant-related hospitalisations per day without new rules, the document said.

The UK Health Security Agency said 568 cases of Omicron have been confirmed, up 131 since Tuesday’s figure.

Sage member Professor Neil Ferguson, from Imperial College London – whose data was instrumental to the UK going into lockdown in March 2020, said the variant is concerning but it is still unknown what its impact will be on severe disease.

He told the BBC : “Certainly case numbers of Omicron are doubling at least every three days, maybe even every two days at the moment, so it’s accelerating very fast and, (to) put that in context, it’s the same if not faster than we saw with the original strain of the virus in March of last year. So it is a concern.

“It’s likely to overtake Delta before Christmas at this rate – precisely when is hard to say.

“We’ll start seeing an impact on overall case numbers – it’s still probably only 2%, 3% of all cases so it’s kind of swamped, but within a week or two, we’ll start seeing overall case numbers accelerate quite markedly as well.”

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