The health secretary said the number of serious illnesses is the “crucial” test – pointing out that the number of people in hospital is currently “flat”, despite the surge of the Delta, or Indian, variant.
“It is too early to make a final decision,” Mr Hancock said, with the verdict due by Monday next week.
But he added: “We’ll keep watching the data for another week or so and, critically, watching that link on the number of cases to the number of people who end up in hospital.
“And it is absolutely true that the number of people ending up in hospital is broadly flat at the moment.”
Mr Hancock revealed that his latest advice is that the Delta variant is 40 per cent more transmissible – a higher figure than about 25 per cent mooted last month.
But, crucially, he said the link between rising admissions and serious Covid cases was being “severed” if not yet “completely broken,” he told Sky News.
Furthermore, the evidence suggested two jabs delivered the “same protection” against the new variant, he said, adding: “The good news is that the vaccine still works just as effectively.”
Mr Hancock also confirmed that under 30s will be called to receive their first vaccine this week, with the target to jab all adults by the end of July set to be hit early.
It came as government data showed cases were still rising significantly, with a further 5,341 lab-confirmed cases of Covid-19 reported in the UK, as of 9am on Sunday.
A further four deaths within 28 days of testing positive for Covid-19 were also reported on Sunday, bringing the UK’s official death toll to 127,840.
The decision whether to complete the roadmap – ending social distancing, mask-wearing and limits on numbers at events – has left a large majority of Britons “worried”, a poll for The Independent found.
Ministers are known to be considering is a pause of at least two weeks, to allow maximum immunity for more double-vaccinated adults to kick in.
Mr Hancock said that, of the four tests set for the decision, cases are “rising slightly” while “the rollout of the vaccine is going incredibly well”.
Later, on the BBC’s Andrew Marr Show, he again stressed the key test, saying: “What matters for opening is the data and the link to hospitalisations.”
However – even if admissions remain flat – the government could opt to keep compulsory mask-wearing in some settings and work-from-home guidance in place.
The greatest pressure from Tory MPs and businesses is to end social distancing rules in venues – while the rule-of-six limit indoors could also be scrapped, Mr Hancock indicated.
He said: “We have said that we will give people enough time ahead of the June 21 date which is pencilled in as the next step – which is to be not before 21 June – and the critical thing is to see whether the four tests we have set have been met.
“That’s in terms of the number of cases, and cases are rising slightly, the number of hospitalisations, which are much more flat. That’s because the third test, the rollout of the vaccine, is going incredibly well.
“Then, of course, we have to look at the impact of new variants and we have seen a very significant impact of a new variant – the Delta variant – over the last month or so.”
This article was amended on 9 June 2021 to clarify that Mr Hancock’s comments related to England.
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