Conservatives in the lockdown-sceptic Covid Recovery Group (CRG) highlighted scientific suggestions that the most vulnerable Britons will achieve a significant level of immunity from the virus three weeks after receiving their first dose of the jab.
Since the Government has pledged to vaccinate the 14 million most vulnerable Britons by February 15, ministers should prepare to ease the rules three weeks later on March 8, the MPs said.
Matt Hancock, the Health Secretary, reiterated this week that the mortality rate is expected to fall by 88 per cent once the most vulnerable cohort, which includes all adults over 70 and the clinically extremely vulnerable, has received an initial dose of the vaccine by the middle of next month.
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It emerged on Tuesday morning that a regional approach to lifting lockdown is being looked at by the Government and could see schools reopen at different times.
Dr Jenny Harries, deputy deputy chief medical officer for England, told MPs there were "likely" to be regional differences in the rules once the nationwide lockdown ends.
Appearing at the Commons education select committee, she said: "On the broad epidemiology, it is highly likely that when we come out of this national lockdown, we will not have consistent patterns of infection in our communities across the country.
"And therefore, as we had prior to the national lockdown, it may well be possible that we need to have some differential application [of restrictions].
"But clearly schools will be right at the top of the priority for trying to ensure that balance of education and well-being is right at the forefront of consideration. I think it's likely we will have some sort of regional separation of interventions."
Steve Baker, the deputy chairman of the CRG , renewed calls for the Government to treat March 8 as a deadline by which regulations should start to be lifted. He said Mr Johnson should set out a roadmap out of the rules ahead of this deadline in order to provide succour to struggling businesses and families.
"We locked down the country and shut down our schools on the basis of a forecast, so why can't we open it up on the basis of one too? It is not sustainable to leave the public and British businesses languishing any longer," Mr Baker told The Telegraph.
"Businesses and individuals desperately need hope and the opportunity to plan our recovery – that's why we need to know our road to recovery as soon as possible.”
The restrictions must be lifted in a way that is "proportionate and safe", he said, but added: "The Health Secretary has told us that the vast majority of hospitalisations and death caused by Covid will be protected against by March 8, so this clearly implies that we should be removing the vast majority of restrictions.
"It is crucial that our response to Covid is proportionate at all times to the harm the disease is capable of causing – which by March 8 should thankfully be hugely diminished if we hit the February 15 vaccination rollout target.”
His intervention came after Mark Harper, the CRG chairman, first issued the demand for the Government to take action to ease the rules by March 8 in an article for The Telegraph.
Mr Harper, a former chief whip, said "nobody is expecting nightclub doors to be flung open on March 8" because it is "obvious that not every restriction can be lifted straight away". However, he added: "People need hope and businesses need a plan in order to survive, especially those in the hospitality, tourism and leisure sectors.
"That's why this week we need a draft plan for the progressive lifting of restrictions from March 8 so that the public, businesses and scientists can use it as the basis for a sensible debate, as the Prime Minister suggested on Friday. That will allow a definitive plan to be published ahead of February 15."
He threw his support behind Mr Johnson's proposal for a "gradual unwrapping" of the lockdown.
A Government source said: "We don't know where the pandemic will be in a fortnight, so it's far too early to be setting dates for when restrictions will be lifted."
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