The prime minister on Monday urged people to avoid unnecessary social contact, whilst avoiding pubs, bars, clubs and theaters.
The announcement came as the government announced 55 people have died from the virus in the UK, with 1,543 testing positive as of Monday afternoon.
On Tuesday, Deputy Chief Medical Officer at Department of Health and Social Care, Jonathan Van-Tam, said we are at the start of an upward curve in the number of people who could be infected with the disease.
He said the UK has made the "right decision" to introduce the social distancing measures now, as opposed to last week.
Just last week, Chancellor Rishi Sunak announced £12 billion of emergency funding in his first budget since taking office. The new package of finance will help struggling businesses through the pandemic.
Mr Sunak will now also appear alongside the prime minister at the daily news conference, the first of which was held on Monday.
Businesses have warned the government allowing them to stay open, whilst telling people to stay away, leaves them vulnerable to financial damage.
Some have claimed, should they be forced to shut they would be exempt from paying rent on premises which are empty of customers.
Coronavirus: Everything you need to know
Leading scientists who have been advising ministers have warned around 250,000 people will die in Britain as a result of the coronavirus outbreak unless more draconian measures are adopted to protect the population.
The Imperial College Covid-19 response team said that even with the "social distancing" plans set out by the Government, the health system will be "overwhelmed many times over".
In its latest report, it said the only "viable strategy" was a Chinese-style policy of "suppression" involving the social distancing of the entire population.
It said such measures would need to be maintained potentially for 18 months or more until an effective vaccine became available.