Government scientists are said to have warned the Cabinet at a virtual meeting this morning that the NHS could be so overwhelmed by the middle of January and that even hospitals may be forced to shut their doors. Prime Minister Boris Johnson said that even using “the most conservative” estimates case numbers are looking “very bad”. The PM warned that a "huge spike" of Omicron is on the way.

       According to The Sun, the briefing was "bleak".

       Ministers were reportedly told that so many doctors and nurses will be off sick by January 15 that the NHS will not be able to operate.

       Their assessment is that there will be too many people reliant on oxygen, even if they aren't in intensive care, with not enough people to administer it.

       The briefing will spark further fears of a fourth national lockdown, as previously restrictions have been brought in as part of an attempt to prevent the NHS from being overwhelmed.

       However, No10 has emphasised that as it currently stands there are "no plans" for any further restrictions.

       The Government implemented Plan B COVID-19 restrictions last week, making face coverings compulsory in most public indoor venues, such as cinemas, theatres and places of worship.

       And from the start of this week, people have been advised to work from home if possible.

       Ministers were also reportedly told at the meeting this morning that shops, pubs and restaurants may also be forced to close due to staff being overwhelmed with Covid.

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       This comes as Tory whips scramble to prevent a rebellion from Conservative MPs over a vote on vaccine passports this afternoon, set to be the largest rebellion of Mr Johnson's premiership.

       The vote will approve the mandatory use of the NHS Covid Pass for entry into nightclubs and settings where large crowds gather.

       Around 80 Tory MPs – amounting to more than a third of the party’s backbenchers – have indicated their intention to rebel, meaning Mr Johnson faces a revolt that could eclipse his largest so far, when 54 Conservatives voted against the tiered system of restrictions last December.

       The plan is expected to pass despite the Tory backlash because Labour will support it.

       In his address to the nation on Sunday, Mr Johnson warned that a "tidal wave of Omicron" is coming.

       He said: "I am afraid we are now facing an emergency in our battle with the new variant, Omicron, and we must urgently reinforce our wall of vaccine protection to keep our friends and loved ones safe.

       "We know from bitter experience how these exponential curves develop.

       "No one should be in any doubt: there is a tidal wave of Omicron coming, and I'm afraid it is now clear that two doses of vaccine are simply not enough to give the level of protection we all need.

       "But the good news is that our scientists are confident that with a third dose - a booster dose - we can all bring our level of protection back up."

       At the moment, just ten people are in hospital with the Omicron variant.

       However, cases are spreading rapidly across the UK.

       The total number of Omicron cases, which have been confirmed by genomic sequencing, stood at about 4,700 on Monday after 1,576 new cases were recorded.

       But the UKHSA estimated the true number of daily infections was far higher based on its modelling.

       The fast-spreading strain now represents 20 percent of cases in England.