The UK government has extended the Covid-19 restrictions for at least the next three weeks.
It comes as the number of people who have died in hospitals following a diagnosis of Covid-19 has risen to 13,729, an increase of 861 on yesterday.
It was the biggest daily rise in five days.
Foreign Secretary Dominic Raab officially revealed the extension at the daily Downing Street briefing this evening.
Mr Raab, deputising for Prime Minister Boris Johnson as he recovers from the illness, said: "Any change to our social distancing measures now would risk a significant increase in the spread of the virus."
He added relaxing rules could cause a "second peak", which would risk increasing deaths "substantially".
Ministers agreed the need to prolong social distancing measures following meetings of the Cabinet and the Government's emergency committee Cobra, amid signs the epidemic in the UK is beginning to peak.
Confirming an extension of the measures for at least three weeks, he said: "Earlier today I chaired meetings of the Cabinet and Cobra to consider the advice from Sage on the impact of the existing social distancing measures.
"There are indications that the measures we have put in place have been successful in slowing down the spread of this virus. But [it] is a mixed and inconsistent picture and, in some settings, infections are still likely to be increasing."
The rate of infection - the R0 value - was "almost certainly below one in the community", meaning infected people were passing the disease on to fewer than one other person on average.
"But overall we still don't have the infection rate down as far as we need to," he said.
Earlier, the health ministry said: "327,608 people have been tested of which 103,093 tested positive," .
The death toll from Covid-19 in England's hospitals rose by 740 today to 12,396, the NHS said.
"40 of the 740 patients, aged between 45 and 93 years old, had no known underlying health condition," it added.
The previous toll was 11,656.
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Earlier, a leading professor of mathematical biology at Imperial College London said the UK would probably have to maintain some level of social distancing until a vaccine for the coronavirus was available.
Neil Ferguson told BBC radio: "We will have to maintain some level of social distancing, a significant level of social distancing, probably indefinitely until we have a vaccine available."
Health Secretary Matt Hancock said earlier that he did not want to "waste" the efforts of the public by lifting the lockdown measures too early, because coronavirus would "run rampant once again".
"I'm not going to pre-judge the formal decision that is going to be taken, however, I think everybody can see that we've been clear that we think that it is too early to make a change," he said.
"And whilst we have seen a flattening of the number of cases, and thankfully a flattening of the number of deaths, that hasn't started to come down yet, and as far as I'm concerned is still far too high."
Mr Hancock added: "I understand those who are calling for an end to the lockdown or some kind of exit strategy to start now, but I think it's just too early for that."
Mr Hancock also said he remains set on the goal of 100,000 coronavirus tests a day by the end of the month.
He said he is "certainly not taking my foot off the accelerator" when it comes to increasing testing.
WWII veteran, 99, completes 100 laps of garden and raises more than £12m for NHS
Captain Tom Moore, a 99-year old British World War II veteran, has completed 100 laps of his garden, raising £12.2 million for the NHS.
Captain Moore was sponsored to complete 100 lengths of his 25-metre garden in time for his 100th birthday at the end of the month.
He originally planned to raise £1,000 for a National Health Service charity after receiving treatment for a broken hip and cancer.
But he is now passed the £12m barrier.
After reaching his target, completed with a guard of honour from the 1st Battalion of the Yorkshire Regiment, Captain Moore said he felt "fine" and that he was glad to be "surrounded by the right sort of people".
"In the last war it was soldiers in uniform on the front line. This time our army are the doctors and nurses (in) uniforms," he told ITV's Good Morning Britain earlier this week.
"We will survive this."
Final 10 laps ....#walkwithtom #TomorrowWillBeAGoodDay
— Captain Tom Moore (@captaintommoore) April 16, 2020
The veteran has received online support from former Manchester United and Arsenal football captains Rio Ferdinand and Tony Adams, Olympic gold medallist Kelly Holmes, and several charities, television shows and newspapers.
Additional reporting Reuters, PA
