Despite the number of cases rising, the country is continuing to take steps back towards normality, as our Political Correspondent Carl Dinnen reports
"We’ve got to be so cautious,” he added, as he said infection rates were increasing.
“We always knew that was going to happen,” the prime minister said.
Prime Minister Boris Johnson says the data about how much the vaccines protect the public is still too ambiguous to make a final decision on the June 21 unlocking.
“What we need to work out is to what extent the vaccination programme has protected enough of us, particularly the elderly and vulnerable, against a new surge, and there I’m afraid the data is still ambiguous.
“The best the scientists can say at the moment is we just need to give it a little bit longer.”
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"I'm sorry that's frustrating for people, I know that people want a clear answer about the way ahead for June 21st.
"But at the moment we've just got to wait a little longer."
Mr Johnson also said the government would "try and allow people to travel" but that they have to be "cautious" and will have "no hesitation in moving countries from the green list to the amber list to the red list if we have to do so."
He added: "The priority is to continue the vaccine rollout, to protect the people of this country.
"One thing is clear from the data, two vaccines really are helpful in protecting you and your family against the virus so get your second jab," encouraged Mr Johnson.
Professor Sir John Bell, regius professor of medicine at Oxford University, agreed "the data at the moment is ambiguous" but said his suspicion was that the country "won't see a lot of real trouble."
He added he suspected "we'll see a few more hospitalised patients, but we wont see a lot of real trouble but that's really a guess, we’ve got to look at the data."
"I wouldn’t make a decision based on what I’ve seen today in either direction."
Professor Anthony Harnden, deputy chair of the Joint Committee on Vaccination and Immunisation (JCVI), said the data from the vaccination programme looked "very promising".
He told ITV News, "the majority of people in hospital at the moment with severe Covid have not received two doses of the vaccine."
Professor Anthony Harnden warns about high infection rates leading to new variants emerging.
But he warned that increasing cases of the virus could lead to the emergence of new variants, "there are a lot of members of the younger community that are unvaccinated at the moment and should infection rates rise, there is always the possibility that new variants could emerge."
Asked if the Government was considering keeping some restrictions such as mask wearing and work-from-home guidance after June 21, Mr Hancock said further decisions would be made in the coming weeks.
"There is nothing in the data to suggest we are definitively off track but it is too early to make the decision about June 21, step four in the road map.
"We'll make that decision based on more data in the next week to 10 days, ahead of June 14, as we've set out."
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Asked whether plans for vaccine passports would be scrapped, Mr Hancock said certification would be necessary for international travel "because some countries have already set out that they require proof that you've been vaccinated, and that means being able to prove with authority that you've had one of the jabs and confidence in which jab accepted for that proof - which is a matter for each individual country."
He added: "When it comes to using certification for domestic purposes, that is the review that Michael Gove is leading, and we'll come forward with the conclusions of it soon."
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