Close contacts of people who have tested positive for coronavirus will be offered repeated testing rather than being required to isolate under new plans being trialled in Liverpool.
Currently those deemed to have been in contact with a Covid-positive person - such as Prime Minister Boris Johnson - are required to isolate for 14 days.
But the scheme will see people allowed to undergo daily tests for a week and not have to self-isolate unless they test positive themselves.
Separately, Downing Street said there would be an expansion of the mass testing trialled in Liverpool to help areas deemed to have "very high" Covid levels, offering them a direct route out of the harshest restrictions with the Armed Forces drafted in to help with Operation Moonshot.
Liverpool, which was placed in Tier 3, will trial the repeated testing scheme starting on Monday, with the Government looking to roll it out across the NHS and care homes in December, and the rest of the UK by January.
Community testing has already been used in the city, with more than 200,000 people undergoing rapid lateral flow tests which produce results within 30 minutes.
The pilot of mass coronavirus testing in Liverpool found 700 positive cases which would have not been detected otherwise, Public Health England director Dr Susan Hopkins said last week.
Downing Street said the testing, along with restrictions on movement, has led to a drop in Covid cases in the area.
Meanwhile, the Government is looking to roll out testing in care homes next month which, it says, will allow each care home resident in the country to have up to two visitors who can be tested twice a week with physical contact permitted.
It is not yet known what areas are destined for Tier 3, with ministers preparing to outline the details on Thursday.
But Downing Street has said a greater number of areas are expected to enter the higher tiers in order to preserve the gains made against Covid-19 during the lockdown.
Additional testing plans also include all staff working in food manufacturing, prisons and the vaccine programme being offered weekly testing from next month.