It could be six months before life in the UK returns to "normal", England's deputy chief medical officer has said.
It comes as a further 209 people have died with coronavirus, taking the total to 1,228.
Speaking at the government's daily coronavirus briefing, Dr Jenny Harries said: "This is not to say we would be in complete lockdown for six months."
She continued, the UK had to be "responsible" in its actions and reduce social distancing measures "gradually".
There are now 17,089 confirmed cases in the UK. The government has said it is ramping up testing for frontline hospital staff who have symptoms, or who live with people who have symptoms.The total number of people tested for the virus in the UK was 120,776, as of Saturday morning.
Critical care doctors and nurses will be prioritised first, with testing expected to follow for A&E staff, paramedics and GPs.
In Wales, Scotland and Northern Ireland, health workers are already being tested.
About 20,000 retired doctors and nurses are set to return to the NHS, Prime Minister Boris Johnson has said.
More than 750,000 people have now signed up to help the NHS during the crisis - three times the number the government asked for.
People not taking the virus seriously
Meanwhile, police were left "in absolute shock" after finding 25 adults and children having a "massive party".
Everyone was dispersed and the hosts "dealt with" after social-distancing rules were breached in Derby. It comes after Derbyshire Police was criticised earlier in the week when it released drone footage of people in pairs rambling in the Peak District.
Meanwhile, Communities Secretary Robert Jenrick announced that all parts of the country are now on an “emergency footing” and said that the first 50,000 food parcels are to be delivered to the most vulnerable this week.
Mr Jenrick said in the briefing that the government is bringing together senior members of the emergency services, with local authorities and the NHS to lead communities through this challenging period, from Cornwall to Cumbria. Members of the armed forces will be embedded in each of these groups, in a move not seen since "World War Two".
Deliveroo and other food chains to provide food to NHS staff
The food delivery service Deliveroo says it will make half a million meals available to NHS staff for free during the coronavirus crisis.
The London-based company has already received pledges of 350,000 free meals from partner restaurants to provide to frontline workers.
Elsewhere,the first of three new testing labs are expected to start work to process 800 samples, the government has announced. Samples will be taken around the country, initially focusing on coronavirus hotspots such as London.
Dozens of universities, research institutes and companies are lending equipment for the labs.