Boris Johnson's road map out of lockdown is set to reach step four on June 21, which would see all legal limits on social distancing removed.
But Health Secretary Matt Hancock said the emergence of the Indian variant – also known as the Delta variant - has made the “calculation” on whether to proceed with unlocking “more difficult”.
Cases of the Delta variant are estimated to be doubling every four and a half days in parts of England, new data suggests.
Matt Hancock says the Delta variant has complicated the unlocking of restrictions.
The Health Secretary told MPs "one day soon freedom will return," but admitted it is too early to say whether England's remaining coronavirus restrictions will be lifted June 21.
Is a delay needed?
Downing Street has said the data emerging over the coming week will be “crucial” in deciding whether the remaining restrictions can end, but added there was "nothing in the data” to suggest a delay would be needed.
Boris Johnson has told members of his Cabinet that the data needs to continue to be scrutinised ahead of any decision on lifting Covid restrictions.
The PM told ministers that “while the relationship between cases and hospitalisations has changed, we must continue to look at the data carefully ahead of making a decision on step four”.
How long would there be a delay for?
It has been reported that Boris Johnson is considering delaying freedom day by at least two weeks until July 5 in order to allow more people to be fully vaccinated against the Delta variant.
Mr Hancock also implied some measures may remain in place after June 21.
This could include further working from home, social distancing in bars and restaurants and mask wearing.
If the Government decides not to proceed with step four of the road map, some indoor venues such as nightclubs would not be allowed to reopen as planned.
Limits on audiences in theatres and cinemas may also remain in place.
What restrictions should be easing after June 21?
As outlined in the Government's roadmap out of lockdown, all legal limits on social contact will be removed from June 21.
It is hoped that the last handful of indoor venues that remain closed, including nightclubs, would reopen and restrictions on large events and performances, and limits on weddings and other life events would cease to apply.
What is allowed currently?
The Government pushed ahead with step three of the road map on May 17, meaning most legal restrictions on meeting others outdoors were dropped.
People are allowed to meet others inside too, though the rule of six or two households applies.
Inside dining returned in restaurants and customers are no longer required to purchase substantial meals with alcoholic drinks, nor to stick to a curfew.
Gyms reopened and certain larger performances and sporting events in indoor venues were allowed to resume.
People enjoying a drink at a bar in London PA
Up to 30 people are able to attend weddings, receptions and wakes, as well as funerals.
When will we know a delay be announced?
Mr Hancock told MPs: "It is still too early to make decisions on step four. The road map has always been guided by the data and, as before, we need four weeks between steps to see the latest data and a further week to give notice of our decision."
Prime Minister Boris Johnson is due to make a decision shortly on whether England can go ahead with full reopening on June 21.
Speaking during a visit to Cornwall, Mr Johnson said ministers would be “driven by the data”.
Who supports a delay?
A number of MPs and scientists have suggested a delay to Freedom Day, with a Whitehall source suggesting Chancellor Rishi Sunak was willing to accept postponing the plans.
Boris Johnson is set to make a decision on the unlocking of further restrictions on June 21.
Professor Neil Ferguson, from Imperial College London, whose modelling was instrumental to the first lockdown in March 2020, suggested that delaying the road map for England could have benefits in ensuring more people have second vaccines.
What about in the other UK nations?
As of Monday in Wales, groups of up to 30 people can meet outdoors, including in private gardens, while up to three households will be able to meet indoors.
The Welsh Government is yet to give a date for the reopening of larger venues providing live performances or for events such as outdoor music festivals.
Plans to ease lockdown restrictions in much of Scotland have been paused, but the rules in Glasgow, which remained at level three for longer, were relaxed on Saturday.
Restaurants, cafes, bars and other hospitality venues in Northern Ireland can operate indoors, with six people allowed to sit together from unlimited households with table service only.