Boris Johnson will host a press conference in Downing Street on Wednesday afternoon, amid warnings of a “staggering” spread of the Omicron variant.
MPs voted on Tuesday in favour of bringing in the government’s Plan B restrictions, but 100 Tory MPs rebelled against the prime minister.
Speaking during PMQs, Johnson said the measures were “balanced and proportionate and right”.
But Labour leader Keir Starmer said the vote had exposed the weakness of a premier who had lost the trust of the public and of his own MPs following reports of parties last Christmas in No.10 in breach of Covid regulations.
“We cannot go on with a prime minister who is too weak to lead, so will the Prime Minister take time this Christmas to look in the mirror and ask himself if he has the trust and authority to lead this country?” he said,.
It came as Dr Jenny Harries, chief executive of the UK Health Security Agency, warned Omicron was “probably the most significant threat we’ve had since the start of the pandemic”
She told parliament there would be a “staggering” number of cases in the next few days compared with what has gone before.
Elsewhere, Professor Adam Finn, from the University of Bristol and a member of the Joint Committee on Vaccination and Immunisation (JCVI), told BBC Breakfast the wave of Omicron is just taking off across the country.
He said: “The wave is coming very fast and in fact alarmingly fast – if anything faster than ever. So it really is a race at the moment.
“The more immunity that we’ve all got the less of a problem this is going to be, but I’m afraid it is going to be a serious problem either way.”