Boris Johnson has called on Brits to “take advantage of this moment” as Covid restrictions relax to “play sport, to take exercise, to have fun and build our national resilience” to the virus.
But the prime minister also preached caution as he refused to rule out a return to lockdowns in the future, saying “we have got to remain humble in the face of nature”.
Speaking at the first press conference from the new £2.6m Downing Street studio, Johnson warned that cases are no longer falling as rapidly as they have been, and that efforts must still be made to contain the virus.
"Already because of the relaxation that we've seen, almost certainly because of the opening of schools again, you're starting to see some of those graphs slightly curl a bit like old British Rail sandwiches, moving upwards a little bit in the younger groups," he said.
Johnson also referenced the deadly third wave taking hold in European countries including Italy and France, urging people not to be complacent.
"You've seen what's happening on the continent and we've seen that happen before, that's why it's so vital that we do what we're doing right now,” he continued.
Yesterday marked step 1B in the government’s roadmap to unlock the coronavirus measures, which see a return to the ‘rule of six’ outside and the re-opening of outdoor sport and leisure.
Asked if he could rule out a return to blanket restrictions the PM said yes, but with "at least two very important provisos".
"Yes, if everybody obviously continues to obey the guidance with sufficient caution and we continue to work together to keep the virus under control, get it down, in the way that we have," he explained.
"If the vaccine rollout continues and the vaccines continue to be as effective as it looks as though they could be, or looks as though they are."
Johnson added: "I don't see anything in the data right now that would cause us to deviate from the road map.
"We have got to remain humble in the face of nature, and we have got to be prepared to do whatever it takes to protect the British public."
Appearing alongside him, England's chief medical officer Chris Whitty said there is a "high likelihood" transmission rates will increase when restrictions ease.
"But, and this is the big but, the point the prime minister was making that has been stressed repeatedly, is that if people stick to social distancing rules and they are outside, the risk of transmission is massively lower than if they are very close together and inside,” he added.
"Provided people stick to outdoors and at a distance if it's people who are not in their households, the impact in terms of an uptick should be modest.
"I think it would not be realistic to think there will be no impact, and that is something we are all aware of.”
In his comments at the start of the briefing Johnson announced “a potentially significant new weapon in our armoury against Covid” will be made in the northeast.
He said the Vaccine Task Force has reached an agreement with the pharmaceutical giant GlaxoSmithKline to “finish and bottle” the Novavax version of the vaccine at its plant in Barnard Castle.
The government currently has between 50 and 60 million doses of it on order, though it is still subject to approval by the UK’s medicines regulator.
The PM said it is important we “continue flat out to build the immunity of our population”. N that the UK has passed the 30-million mark of first doses, he played down any potential supply issues.
"There isn't any need to worry about shortage of Pfizer for the second dose as far as we can see at the moment,” he said.
"We're going to continue to roll that out and supply that, and, as I said, April is going to be the second dose month.
"It's very important that everybody gets their second dose."
Johnson added: “There is one other way we can all build our own individual defences against Covid and enjoy ourselves at the same time – and that is to take more exercise.
“So I am personally thrilled that I will be able to play tennis, for instance, and without being remotely preachy I do hope that we can take advantage of this moment and the beautiful weather to play sport, to take exercise, to have fun and build our national resilience in that way too.
“And remember that outdoors is generally much safer than indoors and the way to continue on our cautious but irreversible roadmap to freedom is to follow the rules and remember hands, face, space and fresh air.”
Alain Tolhurst is chief reporter at PoliticsHome, where this story first appeared.