Other restrictions that have been introduced as part of Plan B are a return to working from home where possible as of Monday and compulsory face coverings in most public indoor venues, although hospitality settings will be exempt.

Paul Holmes, the MP for Eastleigh and Priti Patel’s parliamentary private secretary (PPS), has suggested to constituents that he could defy the party line over the proposals. Asked on social media how he planned to vote, Mr Holmes said: “I’m assessing what ministers have to say and haven’t yet decided.

“I’m not going to be rushed into making a statement until I’ve read the evidence and taken the time to speak to ministers.”

‘First step towards another lockdown’

Another PPS, who asked to remain anonymous, told The Telegraph: “I just can’t vote for the second [regulation] because I’m on record saying multiple times how much I oppose vaccine passports. There are too many parliamentary private secretaries that can’t vote for these statutory instruments.

“I feel this is the first step towards another lockdown. God knows why they are forcing loyal Boris supporters like me to vote for something we fundamentally don’t believe in.”

The PPS is thought to be one of up to half a dozen ministerial aides who will not support the regulations on vaccines.

A second PPS added: “I won’t rebel because I think it is the right thing to do, but the number of my colleagues who don’t agree is very high indeed.

“I think people are going to say to their whips and to No. 10: ‘We’ll support you here because we think these measures are quite modest, but no further.’”