Boris Johnson’s “mismanagement” of the easing of virus restrictions risks a second wave of infections, Labour leader Sir Keir Starmer has warned.
In a Guardian interview, he urged the PM to “get a grip” and restore public confidence in ministers’ handling of the coronavirus pandemic.
But No 10 said it was proceeding with caution to secure a safe recovery.
It comes as the government is to outline further details of its quarantine plans later.
Home Secretary Priti Patel is to tell MPs that the proposals – which have been met with criticism from many Conservative MPs – are necessary to avoid the risk of another wave of coronavirus infections.
From Monday, the majority of those arriving in the UK will be told to self-isolate for 14 days.
But Portugal’s foreign minister has told the BBC that his government is talking to Home Office officials about a so-called “air bridge” agreement so that tourists returning from his country can avoid the restrictions.
In the Guardian, the Labour leader also said there was a growing concern that Mr Johnson was now “winging it” over moves to reopen schools and relax shielding advice.
Echoing Sir Keir’s criticism of the government, shadow Cabinet Office minister Rachel Reeves told BBC Radio 4’s Today programme: “We have seen an exit from the lockdown with no strategy to make it work.”
The Labour MP said the easing of lockdown restrictions was “the time of maximum danger” and that the party was calling for an “effective” test, trace and isolate strategy, “fast access to testing” and “clear” public messaging.
Mr Johnson and Sir Keir will later go head-to-head at Prime Minister’s Questions for the first time since the Dominic Cummings row erupted.
Health Secretary Matt Hancock has suggested the UK is beginning to “win the battle” against the virus, which has now claimed the lives of nearly 40,000 people, according to the government’s daily case figures.
Separate data released by the Office for National Statistics on Tuesday suggested the number of people dying each week linked to the virus has dropped to its lowest levels in the UK since March.
But some scientists, public health experts and opposition politicians have warned that Monday’s easing of restrictions – which saw the partial re-opening of primary schools, the resumption of some sports, the re-opening of covered markets and new freedoms for those previously shielding to leave the house – are premature.
The changes came despite the fact the Covid-19 alert level has yet to be officially lowered from four to three.
’10 times worse’
Sir Keir said while Labour wanted to see society re-open and businesses begin to get back on their feet, he had deep misgivings about the approach in England, compared with that in Wales and Scotland.
He said children had returned to schools before the system for identifying new cases and tracing their contacts was fully up and running.
He also complained that public health officials had been given no notice of the changes to shielding advice for the most vulnerable – which was announced a month before a review had been due to take place.
“After a week or more of mismanagement, I’m deeply concerned the government has made a difficult situation 10 times worse,” he said. “We’ve called for an exit strategy. What we appear to have got is an exit without a strategy.”
He warned that trust in the government had been “burnt” at a crucial time by the controversy surrounding the PM’s chief adviser Dominic Cummings and whether he broke the lockdown rules.
“Like many people across the country, there is a growing concern the government is now winging it,” Sir Keir said.
“At precisely the time when there should have been maximum trust in the government, confidence has collapsed.
“I am putting the prime minister on notice that he has got to get a grip and restore public confidence in the government’s handling of the epidemic.
“If we see a sharp rise in the R rate, the infection rate, or a swathe of local lockdowns, responsibility for that falls squarely at the door of No 10.”
Asked about the likelihood of a second spike in infections on Tuesday, England’s national testing co-ordinator Professor John Newton said it was “patchy” and any resurgence was likely to be “localised”.
But leading epidemiologist Neil Ferguson, whose modelling the government relied on in the first phase of the outbreak, warned that infections in hospitals and care homes are spilling into the community and sustaining the outbreak to the point that cases will remain steady until September.
A Downing Street spokesman said its focus was on “helping the country recover safely from coronavirus and restoring the livelihoods of millions of people across the country”.
“Now is the time to look to the future and not the past, as we continue to fight this virus while taking cautious steps to ease restrictions. The PM looks forward to hearing any concrete proposals Labour has to offer.”
The BBC understands the PM has established two new cabinet committees to support the next phase of the Covid response – one overseeing the strategy for the recovery and the other the delivery of policy.