The prime minister, however, insisted “it’s looking good” for the government’s plan to end all remaining legal restrictions in England on 19 July – something Mr Johnson has referred to as the “terminus point”.
Last week, the chief medical officer, Professor Chris Whitty, urged the health service to brace itself for a difficult winter, saying it was his expectation “we will get a further winter surge” of coronavirus, or a spike in cases of flu.
“Either we, will have a very significant Covid surge, people will minimise their contacts and we will have less respiratory viruses, or people will be back to a more normal life, there will be some Covid but on top of that we will go back to having a flu surge, and RSV surge in children, and so on,” he said last week.
Pressed on the possibility of another surge of the virus in the winter months and whether he would rule out future lockdowns, Mr Johnson told reporters on Monday: “You can never exclude that there will be some new disease, some new horror that was simply haven’t budgeted for, or accounted for.”
“But looking at where we are, looking at the efficacy of the vaccines against all variants that we currently see – so Alpha, Delta, the lot of them, Kappa – I think it’s looking good for 19 July to be that terminus point.
“I think what the scientists are saying is that things like flu will come back this winter, we may have a rough winter for all sorts of reasons, and obviously there are big pressures on the NHS,” Mr Johnson added.
“All the more reason to reduce the number of Covid cases now, give the NHS the breathing space it needs to get on with dealing with all those other pressures, and we are certainly going to be putting in the investment to make sure that they can.”
The prime minister also played down suggestions that restrictions on overseas travel could be lifted later this summer as more people receive a second dose of a Covid-19 vaccine, stressing it would be a “difficult year” for travel.
On a visit to a laboratory in Hertfordshire, he said: “I want to stress that this is going to be – whatever happens – a difficult year for travel.
“There will be hassle, there will be delays, I am afraid, because the priority has got to be to keep the country safe and stop the virus coming back in.”
Speaking earlier, the cabinet minister Kwasi Kwarteng also insisted the government would always “err on the side of caution” and played down any prospect of easing restrictions ahead of 19 July.
When Mr Johnson announced last week that the final stage of lifting England’s Covid measures would be delayed due to a surge in the Delta variant, which was first detected in India, he also told the public there would be a review after two weeks, on 5 July.
Pressed on the date, the business secretary, who said he hoped for “some type of normality” on 19 July, told Sky News: “I think between you and me, I would always err on the side of caution and I would look to 19 July.
“It could be before, but I think that’s unlikely. Well, I don’t know, that’s just my guess. Generally, we’ve stuck to the dates that we’ve said.
“I remember in the previous dates, there was a lot of push to try to get the dates 12 April earlier, the 17 May earlier. That didn’t happen.”
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