Sajid Javid has not ruled out plans for a two-week circuit breaker after Christmas, as he accused those unwilling to have the vaccine of having a "damaging impact" on society.
When pushed on reports that ministers are drawing up plans to introduce more restrictions after Christmas, the health secretary told Sky News' Trevor Phillips on Sunday programme the government will "do what is necessary", but that any change must be "backed up by the data".
He added that ministers are discussing the latest coronavirus data "almost on an hourly basis" with scientific advisers.
Rumours of more restrictions
"We've shown in the past as government in dealing with this pandemic that we will do what is necessary but it's got to be backed up by the data," the health secretary said when probed on any possible plans.
"We are watching the data and discussing it with our scientists and our best advisers almost on an hourly basis. And we will monitor that very carefully. We will keep the situation under review."
He also confirmed that Parliament would be recalled if the government believed introducing further restrictions was necessary adding that "it would have to be a decision for Parliament".
Conservative MP Peter Bone told Sky News that MPs should be in Parliament next week, adding: "I don't want to eat mince pies and drink tea when there is a crisis."
Mr Javid's comments came after senior government scientists suggested that extra restrictions are needed "within days" to prevent hospitals from being overwhelmed by Omicron.
In a tweet on Sunday morning, Prime Minister Boris Johnson said his government is "throwing everything at this virus".
The Sun newspaper suggested possible tougher measures could be imposed after Boxing Day - but that a contingency plan had not yet been presented to ministers.
Scientists and medical experts issue warnings
Asked if the scientific data suggests further restrictions are needed right now by Sky's Trevor Phillips, Professor Sir Mark Walport, a member of the Scientific Advisory Group for Emergencies (SAGE), said: "In a word, yes."
He said infections are "rising fast" and there needs to be time allowed for recently administered vaccines and boosters to take effect.
"We need to act to hold down the rate of hospital admissions, reduce the pressure on the workforce - and of course a lot of people are off sick at the moment - and most importantly of all, give people the chance to get vaccinated, to get boosted, and allow time for those vaccinations to have effect."
Sky News understands experts who produce advice for ministers believe there are now "hundreds of thousands" of infections every day, many more than the number of official cases recorded on the daily dashboard.
On Saturday, the British Medical Association warned that almost 50,000 doctors, nurses and other NHS staff in England could be off sick with COVID-19 by Christmas Day if the government fails to introduce any further measures to stop the spread of the virus.
It is urging the government to now introduce further measures, above and beyond its booster strategy, to stem the spread of the virus - including reducing levels of social contact.
The group said that the consequences of the NHS becoming incapacitated over the Christmas period "do not bear thinking about".
Projections considered by the SAGE advisory committee on Thursday show that hospitalisations are expected to increase from their current level of 900 a day to between 1,000 and 2,000 a day by the end of the year.
They are likely to peak in January at well over 3,000 every day, even with the current Plan B restrictions.
Speaking to the BBC's Andrew Marr Show, Mayor of London Sadiq Khan said it is now "inevitable" that more restrictions will need to be introduced and that there "must, must, must be a major package of support for our hospitality, culture, and retail".
Javid criticises the unvaccinated
The health secretary also told Sky News that 10% of the population - more than five million people - have still not taken up the offer of the vaccine, and that around nine out of 10 of those needing the most hospital care were unvaccinated.
"They must really think about the damage they are doing to society... they take up hospital beds that could have been used for someone with maybe a heart problem, or maybe someone who is waiting for elective surgery," Mr Javid said.
"But instead of protecting themselves and protecting the community they choose not to get vaccinated. They are really having a damaging impact and I just can't stress enough, please do come forward and get vaccinated."
Meanwhile, shadow health secretary Wes Streeting suggested that Labour was meeting with experts to gain an informed view on coronavirus, but would not be drawn on whether Labour would support any new lockdown measures
Mr Streeting said that after SAGE documents were released on Saturday the "question is why is it, having received that advice on Thursday, the prime minister has said nothing, done nothing".