Boris Johnson is expected to examine crucial hospital data on Monday before making any new announcement on Covid measures, but has no plans to recall his cabinet, with ministers still deeply sceptical of further legal curbs. Sources said the prime minister would “take stock” after being encouraged by improving data on Friday, a sign that No 10 is leaning away from stricter curbs in England, but Downing Street sources said he would act quickly if there were new causes for concern. Instead, Johnson will receive only his regular data briefing over the bank holiday with England’s chief medical officer, Prof Chris Whitty – expected to be knighted in the new year honours – and the chief scientific adviser, Sir Patrick Vallance. Key evidence that the government will examine on Monday includes data on the length of stay in hospitals, the transition rates to ICU and new death figures. There is concern among some government figures about undeclared positive cases – including those asymptomatic but also those isolating after a lateral flow test whose results are not recorded by the NHS because they do not take a PCR. However, cabinet ministers are still highly sceptical of further legal restrictions, a week after a tense three-hour cabinet meeting in which the majority pushed back against any new curbs. One cabinet minister said the positive data on Omicron’s severity – a Health Security Agency analysis found those catching Omicron are 50% to 70% less likely to need hospital care compared with previous variants – proved they had been right to hold out. “The data so far is still struggling to be persuasive of legal changes to be required,” one cabinet minister said. Another said it was “right that we didn’t rush last time given positive, early data”. But a hospital doctors’ trade union urged ministers to implement further measures without delay to help the NHS, including limits on household mixing and table service only in hospitality venues. Dr Paul Donaldson, the general secretary of the Hospital Consultants and Specialists Association, warned Johnson that “it would be ludicrous” not to respond more decisively to Omicron, and that Christmas mingling would inevitably have spread Covid. “There is a high probability we are moving too late,” said Donaldson, a consultant microbiologist. “We will soon start to see the impact of Christmas. We are holding out hope that hospitalisations are at the lower end of projections. But given the uncertainty we face it would be ludicrous not to take additional precautions,” he added. The HCSA also wants to see social distancing measures applied in retail and hospitality settings, such as mask-wearing, table spacing, limits on capacity and queueing systems, as well as social distancing and bubbles in all schools and continued working from home. The NHS Confederation, which represents health service trusts in England, said any further steps would help the NHS, given the rising number of hospitalisations and staff off sick due to the virus. There were 1,171 people admitted to hospital across the UK in the previous 24 hours, the government disclosed on Friday. “Any new restrictions which are brought in to help ease the pressure on the NHS need to be clearly explained to the public. Confusion and complacency can make any new restrictions ineffective,” said Matthew Taylor, its chief executive. The prime minister has pledged to his restive backbenchers, a significant number of whom rebelled over the last set of restrictions, that he will recall parliament before implementing new restrictions but it is possible any vote could be retrospective, should the decision be taken later in the week. Johnson faced significant opposition from his cabinet before Christmas during a three-hour meeting where the decision was taken to delay any new curbs until after the festive weekend. The transport secretary, Grant Shapps, the foreign secretary, Liz Truss, and the business secretary, Kwasi Kwarteng, were said to be the most sceptical of restrictions, while the levelling up secretary, Michael Gove, and culture secretary, Nadine Dorries, have urged the most caution. On Friday, papers released from government scientific advisers showed modelling for the impact of implementing “step 2” restrictions from Tuesday – a date now unlikely to be practicable. That would mean an end to indoor gatherings and introducing the rule of six outdoors, with bars and restaurants only able to serve outdoors. The modelling suggested that restrictions could reduce deaths by 18% if kept in place until mid-January or 39% if retained until the end of March. Cabinet resistance to further restrictions is also likely be deepened by the collapse in Johnson’s own poll ratings over the scandal of No 10 Christmas parties and deep rifts with his own party over plan B restrictions to enforce home working, mask-wearing and new Covid passes for large venues. Speaking to the Observer on Sunday, Conservative MPs suggested that those who wished to eventually replace Johnson should resist further Covid restrictions. Johnson and the education secretary, Nadhim Zahawi, are said to be determined that schools reopen on time in January. Step 2 restrictions would allow schools to remain open, as well as non-essential shops, subject to social distancing rules. New coronavirus restrictions come into force from Monday in Wales, Scotland and Northern Ireland. From Boxing Day, a maximum of six people will be allowed to meet in pubs, cinemas and restaurants in Wales, as well as other restrictions on numbers for larger events. In Scotland, up to three households can meet, with 1-metre distancing between groups at indoor and outdoor venues such as bars, restaurants, theatres, cinemas and gyms. Table service is also required at places where alcohol is served. Northern Ireland is also recommending restricting socialising to three households, while up to six people can meet in pubs, bars and restaurants. However, there are serious concerns in the NHS that the large number of frontline personnel falling sick as infections spiral because of Omicron is hampering the service’s ability to provide care. Staff absences in England due to Covid have been soaring during December, the latest official figures showed last Thursday. The number of days lost to illness caused by Covid went up by 38% to 124,855 in the week to 19 December, while the number of staff off sick rose by 54% from 12,240 to 18,829, both compared with the previous week. At some hospitals in London, which has been hit first and worst by the new variant, the number of staff off ill with Covid has trebled since the start of the month, NHS England’s figures showed. Taylor said that the service was facing a “double emergency” of sharply rising staff absences because of illness at the same time as the demand for hospital care was rising. Chris Hopson, the chief executive of NHS Providers, has said that the loss of frontline staff to sickness is “a big worry” for hospital bosses who are facing growing demand from patients, especially as the NHS in England has almost 100,000 vacancies anyway.