Downing Street denied it was an emergency meeting, saying ministers were being updated on a fast-changing situation.
It comes after the Government’s Scientific Advisory Group for Emergencies (Sage) warned daily hospital admissions could reach 3,000 without further restrictions.
Downing Street did not deny reports that a number of ministers – including Chancellor Rishi Sunak – have pushed back against calls for action without more evidence of the impact the virus would have.
The Prime Minister’s official spokesman said it was part of the job of ministers to scrutinise any advice they were given.
“We need to strike the right balance between protecting lives and livelihoods. That is what we are focused on,” the spokesman said.
“This is a fast-moving situation. There are significant gaps in the data we have relating to this variant.
“We are working to get more clarity on what impact it has on things like severe illness, hospitalisations and deaths.
“It is one of the roles of ministers to scrutinise any advice and evidence provided, and consider it in the round. That is the function of Cabinet.”
Earlier, Deputy Prime Minister Dominic Raab refused to rule out the possibility that additional measures could be required before Christmas – now less than a week away.
“I just can’t make hard, fast guarantees,” he told Sky News.
He added: “The Prime Minister has got some very difficult decisions to take and I’m sure he’ll be thinking very hard at them.”
The Government has said that it will if necessary recall Parliament to allow MPs to vote on any new regulations it proposes for England.
However, that could prove politically problematic for Mr Johnson, with not only senior ministers objecting to any further controls.
Last week Mr Johnson suffered the biggest backbench rebellion of his premiership with 100 Tory MPs voting against rules requiring Covid passports for entry into nightclubs and other venues.
Any additional proposals could spark another revolt at a time when the Prime Minister is politically weakened by the ongoing row over parties in Downing Street last Christmas and the Tories’ crushing defeat in the North Shropshire by-election.
Sir Keir Starmer said Labour would again support any additional public health measures that were required but that the Prime Minister needed to come forward with a clear plan to support businesses that were affected and to keep schools open.
“What I want to see is a Government, a Prime Minster, that gets a grip, that puts a plan forward that we can all get behind. But where is he? There’s a vacuum of leadership at the moment,” he said.
“The infighting is going on in the Tory Party when the focus should really be on the public interest and public health. At the moment, my frustration is that the Prime Minister is completely absent.”
Mr Johnson has reportedly been presented with a series of options to tackle the spread of the virus, ranging from guidance asking people to limit indoor contacts, to rules on household mixing, social distancing and a curfew on pubs and restaurants, to full lockdown.
Professor Ravi Gupta, a member of the Government’s New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), said that with 12,000 confirmed cases of Omicron variant in the UK, it could potentially overwhelm the NHS.
“So that’s a really critical situation that we’re facing,” he told Sky.
“Even if the vaccines protect us to a significant degree, then the increased transmissibility and penetration of the virus into communities that we’re seeing already is putting a large amount of pressure (on the NHS) because a very small fraction of a very large number still translates to significant numbers being hospitalised.”
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