The pressure on Boris Johnson over next week’s coronavirus lockdown review is mounting, and mainly from his own MPs.

That much was clear when an exasperated Charles Walker, vice-chair of the influential 1922 Committee, this week reacted to the suggestion that domestic summer holidays may not be possible by telling the prime minister to “get a grip of his cabinet ministers”.

And while there are a range of Tory views on the speed at which lockdown should be lifted, one thing currently uniting backbenchers is a concern about the PM “moving the goalposts” on the criteria for relaxing restrictions.

Despite health secretary Matt Hancock and official scientists resisting the idea, there is a concern that some ministers are leaning further towards, if not fully into, a so-called “zero Covid” strategy as the virus mutates and creates the risk of a vaccine-dodging variant.

Tory MPs worry about “mission creep” – away from just reducing hospitalisations and deaths through vaccinations and towards also keeping case numbers very low, and therefore restrictions in place longer, to reduce the risk of an escape variant emerging, even if those most likely to die are vaccinated.

At least 35 opposition MPs have signed a motion calling for the government to adopt a zero-Covid strategy.

Walker summed up the worries this week: “For crying out loud, we were told weren’t we that the vaccines were the route out of this.”

But it isn’t just lockdown opponents like Walker that are spooked as the PM prepares to review lockdown next week before announcing a roadmap for lifting restrictions on February 22.

The details of who will meet who, to discuss what data, and when, next week are closely guarded, with all but the most senior No.10 aides kept in the loop.

But Johnson is said to be seriously concerned about the emergence of a so-called “black swan” escape mutant, and has been sphinx-like in preparatory meetings with top backbenchers – a departure from his usual aim-to-please approach.

Tory MPs believe the current government strategy for lifting lockdown means opening schools in March, shops in April and hospitality in May, although many want a quicker timetable.

But even those content with that broad timeline are concerned about any intensifying focus on case numbers once the most vulnerable are vaccinated.

One “red wall” MP says they have “no time for this elimination strategy”.

“I think the government has been clear on this but I’d like some clearer statements – we need to be clear that what we are trying to do is stop hospitalisations.

“If we can stop hospitalisations then that’s the yardstick and we’re getting back to normal.”

The MP also dismisses worries about the Oxford/AstraZeneca vaccine offering only minimal protection against mild and moderate cases in people infected with the South Africa variant as “bollocks”.

For most Tories, the line is clear: once enough people have been vaccinated to stop most severe cases, and therefore reduce deaths and ensure there is not undue pressure on the NHS, there is little case for onerous restrictions.

“Basically we’re arguing there about whether or not you get a bad flu,” the MP says.

“Well, if it doesn’t kill you and doesn’t impact the NHS, I am not here to stop you getting ill.

“I don’t want people to get ill and it affects productivity and all the rest of it, but we have just got to blast right through that.”

Some blame Hancock for what they see as a potentially shifting position.

“The positions of some, like Hancock, have hardened massively,” says one Tory source.

“But [chief scientific adviser] Sir Patrick Vallance says Covid will be here forever so I don’t know what his long-term answer is.

“It sounds like an argument for permanent lockdown and quarantine.”

Others however feel the tensions are “overblown” and are born out of a desire of ministers to be over-cautious, to underpromise and over-deliver, after doing the opposite over the past year and suffering the political consequences. 

But the red wall Tory warns Hancock against being too hardline.

“Anybody who thinks the Conservative Party is going to be in a place where they accept substantial restrictions for something that doesn’t kill or hospitalise you I think is for the birds,” they say.

“The only argument for that is doing it to prevent new variants.

“But that seems to me a bit like ‘well if I don’t go out of my house tomorrow I won’t get run over’.

“There is risk in life and we’re going to have to accept some of that risk and I don’t think it would be sensible to try and make that case.”

The suggestion that summer holidays may not happen, even domestically, convinced Walker that the focus is shifting in the government, that the goalposts were moving.

“They’ve not so much been moved as ripped out and carried to another playing field,” he said this week.

Some MPs still wonder if Johnson’s near-death experience with coronavirus means “he hasn’t got the balance in his head” between lockdown restrictions and protecting health.

Sir Geoffrey Clifton-Brown, treasurer of the 1922 Committee, says: “Allowing the lockdown to go on too long is just as serious as undoing the lockdown too quickly.

“One triggers another wave of the virus but the other does huge damage to people’s mental health, individual freedoms, more businesses will never reopen, you’ll be stuck with higher unemployment.”

Many Tories agree that once all the over-50s and clinically vulnerable are given vaccine first doses by May, there is little argument for continuing tough restrictions. The Covid Recovery Group has argued for legal restrictions to be replaced by guidance at this stage.

Clifton-Brown wants hospitality opened sooner, and underlines another headache for the PM – the current laws governing lockdown expire on March 31 and he will face another major Tory rebellion if he tries to extend the most onerous measures further.

It also comes at a time when Johnson is fighting backbenchers on several fronts, including the cladding scandal, and a China-focused argument on whether the courts should rule whether a country is committing genocide.

“I think that you’ve got to be careful with pubs,” Clifton-Brown says.

“Talking about May is completely unacceptable because they’re missing out on the May bank holiday, they are missing out on Easter, this is just completely unacceptable.”

He added: “But I can tell you now that if my hospitality is not being allowed to open until May, I am more than likely to vote against the government.”

The battle over lockdown is taking place across multiple fronts too.

One senior Tory says their “strongest objection” to the restrictions is “the prohibition of seeing children and grandchildren who don’t live with you”.

In any case, many believe that as more parents and grandparents are vaccinated into the spring, it will be difficult to convince people that they cannot see their children or grandchildren.

Given ministers have ruled out domestic vaccine passports, some envisage a scenario where the government has to lift restrictions “a little bit sooner than the medics want them to be” or face mass rule-breaking.

The senior Tory says: “Why should two friends in their 80s, both of whom have been vaccinated, not meet and have a drink or play dominoes or whatever octogenarians like to do?

“They are going to start ignoring it.

“Do you start arresting huge numbers of grannies who have had illegal tea parties with people who are at no risk of infection?”

The red wall Tory adds: “I get a sense people are more willing to accept this lockdown but a lot of people are finding it more difficult and they are only doing it for a limited period of time.

“I just don’t know how you are going to get to a succession of very sunny days in May and June and still say to a load of grandparents: ‘Could you just watch telly for a bit and not see your grandkids?’”

Downing Street’s refusal on Friday to deny reports that social distancing restrictions – and doubts about whether families can hug – are here to stay until autumn are likely to concern lockdown-sceptic Tories.

But others are more sanguine, as long as businesses can operate and power an economic bounce back after the worst recession in 300 years.

“I don’t think we’ll be shaking hands any time soon. I don’t think we’ll be telling people they can’t work from home,” one ex-minister says.

“If we open hospitality I suspect we will also be having the social distancing measures in place as the weather gets better.

“I know a couple of restaurants in my constituency that have applied for tables on the pavement and that could well be the case for most of the summer.

“And we are unlikely to see large numbers of people travelling abroad as well.

“[The vaccine and case rates] are encouraging and we need to open up the economy, particularly hospitality and our domestic tourism sector.

“There are a lot of people with money burning a hole in their pockets.” 

The red wall Tory meanwhile believes colleagues should hold their nerve, because there is a “clear cut way you can see this ending”.

“We are just another three or four weeks away from actually believing it’s going to happen.

“I think we’ve just been all so beaten up by this thing that many times that we can’t quite believe that we are going to be able to stop it this time.”