A major Tory rebellion over Covid vaccine passports is set to pile pressure on Boris Johnson as the embattled Prime Minister struggles to hang on to his authority.
More than 70 Conservative MPs are said to be prepared to vote down Plan B measures on Tuesday to tackle coronavirus this winter as the Omicron strain surges.
Labour has said its MPs will back the plans, which will allow them to pass - but Mr Johnson could face the largest rebellion of his premiership.
Tory MPs have reacted with fury to proposals that would make vaccine passports mandatory for large venues.
The introduction of 'Covid passes' will mean those who are not double-jabbed - or prepared to prove a recent negative test - are barred from indoor venues with more than 500 people, unseated outdoor venues with more than 4,000 people and any venue with more than 10,000 people.
The Plan B measures also include compulsory mask-wearing in most public indoor settings, as well as guidance for employees to work from home where they can in order to stem transmission.
Former Cabinet ministers David Davis, Esther McVey, Dr Liam Fox and Greg Clark are among those to have voiced concerns about the scaling-up of restrictions.
It has also been reported that Cabinet ministers are prepared to resign over the plans.
Education Secretary Nadhim Zahawi tried to calm Tory nerves, saying: “People talk about vaccine passports.
"This is not a vaccine passport. These are high-risk events where we ask people either to take a free lateral flow test or to be vaccinated to attend.”
The government looks set to avoid defeat, however, as Labour is backing the plan.
Labour leader Keir Starmer said he was uncomfortable with the idea of vaccine passports but he saw that they were necessary.
He told the BBC : "I am concerned about the idea of vaccine passports, I’m not comfortable with it, but I’m persuaded that it is necessary, particularly if it’s linked to the alternative of a negative test, which is what a lot of venues have been operating on a voluntary basis now for a very long time.
"I went to Arsenal Football Club yesterday to watch the match, as I always do. That system has been in place on a volunteer basis so we know that it works.
"But am I comfortable with these restrictions and measures? No, I wish it didn’t have to happen."
Tory backbench ringleader Steve Baker said further restrictions were "wrong" and "disproportionate".
He said: "I will vote against vaccine passports, of course I will. I'll vote against extending mask mandates, and I'll vote against mandatory vaccination as a condition of NHS employment.
"I think all these things are wrong, they're disproportionate and there's inadequate evidence that they're required. And I really think this is the crucial point here now - what's on the table is what kind of society we're creating as we go forward."
