BORIS Johnson is facing what could prove to be the largest rebellion of his premiership, with more than 60 Conservative MPs said to be against the imposition of extra coronavirus measures.

The Prime Minister announced on Wednesday he would be triggering his winter Plan B protocols in a bid to buy time in the fight against the Omicron variant of the virus.

Tories have reacted with dismay to the proposals, with tens of backbenchers pledging to vote down plans for vaccine passports to be made mandatory for large venues.

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The introduction of Covid passes in England will mean those who have not been fully vaccinated will not be able to enter indoor venues with more than 500 people, unseated outdoor venues with more than 4000 people and any venue with more than 10,000 people from Wednesday.

England's 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.

The National: Tory MP Greg Clark is among the expected rebelsTory MP Greg Clark is among the expected rebels

Clark, a former business secretary, said the Government had “jumped the gun” in choosing to act before more was known about the impact Omicron could have on hospital admissions.

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Former trade secretary Dr Fox, speaking in a debate in the Commons, said it was “difficult to justify these extra measures”.

Senior Conservatives, including select committee chairmen Tobias Ellwood and William Wragg, have spoken in opposition to the measures while 2019 in-take MPs such as Dehenna Davison and Lee Anderson – who represent so-called former Labour “red wall” constituencies – have announced they will rebel on Tuesday’s vote in the House of Commons.

Former defence minister Ellwood, who chairs the Defence Committee, told Sky News on Saturday: “I’d strongly urge the Government to drop the vote on vaccination passports next week.

“It is not the appropriate tactic to impose on a very weary nation at this time.”

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According to The Sun, former Brexit minister Steve Baker told MPs in the Covid Recovery Group (CRG) – a group of anti-lockdown Tories – WhatsApp chat that ministerial resignations were “likely” during the restrictions row.

Despite the difficulties facing the Prime Minister – who enjoys a majority of around 80 in the Commons – on his own benches, the Plan B vote is almost certain to pass with Labour support.

Asked about the prospect of a Tory rebellion, Communities Secretary Michael Gove said he was “confident” MPs would examine the proposals “seriously, soberly and thoughtfully” in light of the fast way Omicron has been spreading across the UK.

Speaking to broadcasters on Friday, he added: “I’m also confident people will conclude that, on balance, it is right to act.”

Johnson told a Downing Street press conference this week he would like to lift the Plan B measures “no later than early January”.