However, the UK Health Security Agency has said that current guidance requiring NHS staff to self isolate for 10 days if they are in close contact with an Omicron case still applies, but remains under review.
The change comes as prime minister Boris Johnson warned that the UK faced an 'Omicron emergency' - with a 'tidal wave' of cases now sweeping across the country.
When the Omicron variant was detected in the UK, the government said anyone identified as being in close contact with a case of the variant would need to isolate for 10 days, regardless of their vaccination status. Since August, anyone double-jabbed for at least 14 days or aged under 18 has not been required to self isolate if they are a close contact of a confirmed case of COVID-19.
GPs and NHS leaders had raised concerns that automatic self isolation for Omicron close contacts could have a significant impact on the workforce if the variant spread rapidly, which data suggests is happening.
Guidance for NHS staff
Under current guidance, NHS staff who have been in contact with a non-Omicron case of COVID-19 are required to take a PCR test and only return to work if it is negative. They should then conduct daily lateral flow tests for 10 days. If staff are in contact with an Omicron case they need to self isolate for 10 days.
The government said the change for the public was aimed at reducing the pressure on people's everyday lives by scrapping the requirement to self isolate, at the same time as protecting the public by identifying asymptomatic cases.
However, concerns have emerged that a shortage of lateral flow devices could force people to continue with self isolation. Within less than 24 hours of Mr Johnson's announcement, the government website was saying it had run out of lateral flow tests.
Under the new rules, anyone who tests positive on a lateral flow test should take a confirmatory PCR test and if that comes back positive self isolate for 10 days from the date they took the positive rapid test or developed symptoms.
Lateral flow test
The government has also recommended that those identified as a close contact with a case of COVID-19 should 'limit close contact with other people outside their household, especially in crowded or enclosed spaces and with anyone who is more vulnerable'.
Unvaccinated adults must continue to self isolate for 10 days if they are a close contact of a case.
Health and social care secretary Sajid Javid said: 'The Omicron variant is quickly gaining ground in the UK and is expected to become the dominant strain by mid-December. We are taking this proportionate and more practical measure to limit the impact on people’s day to day lives while helping to reduce the spread of Omicron.
'Vaccines remain our best defence and I urge anyone yet to get a first and second jab to come forward and those eligible for a booster to get boosted as soon as possible.'
On 12 December the prime minister announced that booster jabs will now be offered to anyone who received a second dose at least three months ago by the end of December. The target is understood to mean the NHS will need to deliver 1m booster jabs a day by the end of the month.
Mr Javid told the BBC's Today programme that the task ahead means that GP practices will focus solely on delivering urgent appointments and vaccinations until January – although guidance to practices has yet to be published.