The government is “considering” scrapping quarantine requirements for those who have had both vaccine doses.
Downing Street said it was looking at whether to drop all legal self-isolation measures for fully vaccinated people who come into contact with someone who is infected “as part of the post-Step 4 world”.
Ministers had already been considering replacing self-isolation with daily testing depending on the results of a number of pilots currently being carried out.
But officials confirmed this weekend that additional thought was going into making the testing requirement advisory rather than mandatory for those who have had two jabs.
If approved, the plan would not come into force on so-called “freedom day” on 19 July, with sources indicating that the timeline would be “quite a bit later” than the planned date for the end of all restrictions.
That is likely to face opposition given the disruption that isolation may cause over the summer as cases increase.
Several different proposals are understood to be under consideration with no final decisions yet made.
Plans to allow double-vaccinated people to avoid quarantine when travelling back from amber list countries are also being considered with an announcement on the plan due next week.
A scientific adviser has said the problems associated with allowing people who have both jabs to benefit from an exemption “outweigh the potential benefits” and warned that it could cause “resentment”.
Professor Robert West, a health psychologist who is a member of the Scientific Pandemic Influenza Group on Behaviours (SPI-B), told Times Radio: “The most serious problem is that if you have a situation where not everyone has been even offered the vaccine then you’ve already got clearly a huge unfairness.
“When you get unfairness in situations like this, you get resentment and when you get resentment you can get loss of compliance.”
But his assertion has been challenged by other medical experts, who said it would be “perfectly OK” to allow those who are fully inoculated more freedoms.
Dr Bharat Pankhania, a senior clinical lecturer in communicable diseases at the University of Exeter, told BBC Radio 4’s Today programme that vaccines were breaking the link between cases, hospital admissions and deaths, meaning “we can start thinking about other uncoupling measures, such as no need to quarantine after being fully immunised”.
Epidemiologist Professor Christophe Fraser, who advised the Department of Health on test and trace, said a “midway” proposal could be that those who have received both jabs are tested every day instead of undertaking a quarantine period.
The Oxford University academic said he agreed the self-isolation policy “needs to be reviewed in light of the data on the vaccine effectiveness”.
The debate about extra rights for those who have been vaccinated is playing out amid a background of an “alarming” rise in COVID-19 cases in England.
The latest figures from the Office for National Statistics (ONS) show that about one in 260 people in private households in England had COVID in the week to 26 June – up from one in 440 in the previous week and the highest level since the week to 27 February.
The increase has caused leading doctors to urge the government to keep some restrictions in place in England after 19 July in a bid to stem the rate of infection.
The British Medical Association (BMA) said that keeping some protective measures in place was “crucial” to stop spiralling case numbers having a “devastating impact” on people’s health, the NHS, the economy and education.