The prime minister is expected update the country around 5pm after reviewing the latest data on Covid case numbers and hospitalisations from Christmas and New Year.
Professor Sir Chris Whitty, England’s chief medical officer, and the government’s chief scientific officer Sir Patrick Vallance will join Mr Johnson to set out the latest picture.
It comes as the Royal College of Nursing (RCN) called for a more “cautious” approach to curbs in England to bring the country in line with the rest of the UK, as at least six NHS trusts declared critical incidents.
Mr Johnson is also under pressure to cut the Covid self-isolation period for people in England from seven to five days, as business chiefs and hospitality leader warn of mass labour shortages.
However, No 10 has strongly suggested that Mr Johnson will stick with current plan B measures rather than bring in any major changes for England this week.
“At the moment, we don’t see any data that suggests further restrictions would be the right approach – given we know it’s important to strike the right balance between lives and livelihoods,” the prime minister’s official spokesman said on Tuesday.
Asked if the government thought plan B is working, the No 10 spokesman said: “We believe this is the right course – asking people to work from home, use the Covid pass and of course the booster programme.”
Mr Johnson will hold a cabinet meeting on Wednesday morning, and ministers will update parliament on the government’s review of plan B measures later on Wednesday.
Vaccines minister Maggie Throup earlier insisted that “plan B is working” and indicated the government would not heed calls for further curbs. “I don’t see any reason why we need to change,” she told Sky News on Tuesday.
At least six NHS trusts are believed to have declared critical incidents, where chiefs are concerned they may not be able to provide priority services. University Hospitals of Morecambe Bay confirmed on Monday evening an “internal critical incident” and some non-urgent operations and procedures would be suspended.
Matthew Taylor, chief executive of the NHS Confederation, warned against any “politicised attempt” to suggest that things are not difficult. The leader of the body representing trusts said decisions on any further restrictions in January should be driven by data rather than “a kind of political virility symbolism”.
The vaccines minister also said the government would reject calls to reduce the isolation time from seven to five days. “At the moment, actually, we don’t feel it’s appropriate to reduce it any further because we will be very concerned that people will still be infectious and be able to pass on the disease,” Ms Throup told LBC.
But business leaders have warned that staff absences could soon wreak havoc for the economy, as the latest figures show more than one million people in the UK have tested for the virus over the past week.
Meanwhile, headteachers have warned that children returning to school in England on Tuesday face disruption to their learning as the Omicron variant of Covid threatens widespread absences of staff and pupils.
Prof Neil Ferguson, a member of the Scientific Advisory Group for Emergencies (Sage), said a rise in Omicron cases in schools can now be expected. “We expect to now see quite high infection levels – of mild infection I should emphasise – in school-aged children,” he told the Today programme.
But Prof Ferguson also suggested Covid cases should start to drop across the UK in the next one to three weeks. “I think I’m cautiously optimistic that infection rates in London in that key 18 to 50 age group, which has been driving the Omicron epidemic, may possibly have plateaued.”
Asked after a speech in Birmingham whether England’s plan B rules should be tightened, Sir Keir Starmer said: “We hope that we don’t need further restrictions. Obviously, there’s cause for concern because of the numbers.”
The Labour leader added: “We need better leadership from the government because if we’re to keep our schools open – and we must – what we need is many more of our school children vaccinated. We need much better ventilation – and we’ve been saying this for about a year.”
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