Boris Johnson has said “the sun is shining but we’re keeping our umbrella” in the fight against coronavirus, ahead of a landmark relaxation of self-isolation laws and end to free universal testing in England.

The Prime Minister set out the Government’s strategy for “living with Covid” on Monday afternoon after a Cabinet disagreement centring on funding for future surveillance of the virus disrupted his plans.

Speaking later at a Downing Street press conference, he hailed the development of vaccines and treatments for Covid-19 as “possibly the greatest national effort in our peacetime history”.

But he said “we should be clear that the pandemic is not over”, warning “there may be significant resurgences”.

Meanwhile, Professor Sir Chris Whitty, England’s chief medical officer, said the Omicron wave is “still high”, adding: “The rates are coming down but this is still a very common infection.”

He said new variants are anticipated, with some expected to “just disappear”, while others will cause “significant problems”.

Mr Johnson acknowledged there will likely be another variant that will “cause us trouble”, saying he did not want people to think “there’s some division between the gung ho politicians and the cautious, anxious scientists”.

“We have a very clear view of this. This has not gone away.

“We’re able to make these changes now because of the vaccines and the high level of immunity and all the other considerations about Omicron that you’ve seen,” he said.

“But we have to face the fact that there could be, likely will be, another variant that will cause us trouble.

“But I believe that thanks to a lot of the stuff that we’ve done, particularly investment in vaccines and vaccine technology and therapeutics, we’ll be in a far better position to tackle that new variant when it comes.”

He said: “The most important thing is that – and I hope this is the big take out from this… the sun is shining but we’re keeping our umbrella.”

It comes as all coronavirus laws in England, including the legal requirement for people who test positive to isolate, are set to end on Thursday, before free universal testing is scrapped in April.

Those who receive a positive Covid test will still be advised to stay at home for at least five days, but will not be obliged to under law under the plans subject to parliamentary approval.

Sir Chris urged people who test positive for the virus to self-isolate, despite the change in rules.

The most important thing is that - and I hope this is the big take out from this... the sun is shining but we're keeping our umbrella

“As we look at the next weeks, we still have high rates of Omicron and I would urge people in terms of public health advice, and this is very much the Government’s position, that people should still if they have Covid try to prevent other people getting it and that means self-isolating,” he said.

Under the plans announced on Monday, routine contact tracing will also cease on Thursday, as will the £500 self-isolation payments and the legal obligation for individuals to tell their employers about their requirement to isolate.

On March 24, changes to statutory sick pay and employment support allowance designed to help people through the pandemic will come to an end.

Free universal testing will then be massively scaled back from April 1.

Remaining symptomatic testing will be focused on the most vulnerable, with the UK Health Security Agency (UKHSA) set to determine the details.

Mr Johnson rejected the assertion that the end of free testing would add to the looming cost of living crisis in April.

The rates are coming down but this is still a very common infection

“This change in the testing regime won’t come through for a few weeks to come, by which time we hope and expect the incidence will have further declined,” he said.

“I hope that the impact on people will be minimal.”

Earlier, the Prime Minister warned MPs that the “pandemic is not over”, with the Queen’s positive test a “reminder this virus has not gone away”.

But he said there is “sufficient levels of immunity to complete the transition” from laws to relying on vaccines and treatments and individuals making the right choices.

The Government expects a market for lateral flow devices to develop once boxes are no longer available free on the NHS, with individual tests expected to cost a few pounds.

To prevent people stockpiling them before April 1, individuals will only be able to order a box of tests on the NHS every three days instead of every 24 hours.

The Cabinet was due to sign off on the plan on Monday morning, but the meeting was pushed back to the afternoon at the last minute, with the delay understood to centre on Health Secretary Sajid Javid’s demands over how elements would be funded.

The chaos surrounding the policy, which should help shore up Mr Johnson’s support on the Tory backbenches by ending the remaining legal restrictions in a nation that has lived under measures for nearly two years, came as the PM’s authority was undermined by the partygate scandal.

But No 10 ultimately said the Cabinet gave the strategy its “unanimous backing” after a virtual meeting in the afternoon.

One of the factors that influenced the decision was data indicating that the Omicron wave had not resulted in any excess deaths, an indication of the protection offered by the vaccines.

Groups representing vulnerable individuals sounded the alarm over the end to isolation laws, with the Scope charity saying it would usher in a life “living with fear”.

Labour leader Sir Keir Starmer said it was “not a plan to live well” with Covid and will leave the nation “vulnerable”.