Families will be granted five days of looser Covid-19 restrictions to enjoy Christmas with two other households, after a four-nation agreement was struck.
Scotland, Wales and Northern Ireland have backed the plan put forward by Boris Johnson at the weekend – despite fears that infections will rise.
The exemptions will kick in on 23 December, lasting until 27 December, with travel restrictions also relaxed to allow families to meet up.
However, ministers have stamped on hopes of Christmas Day lunches in a pub or restaurant, because get-togethers will only be allowed in a home, a place of worship or outdoors.
People will be able to hug their loved ones – as social distancing rules are removed for the five days – but over-65s in care homes will not be allowed to join their families.
And families will have to nominate the two other households with whom they plan to “bubble” – and will be prevented from changing that decision, to meet with other relatives over the five-day period.
The plan is intended to allow a typical family to enjoy festive meals indoors with both sets of grandparents, or perhaps two groups of friends.
However, it’s likely people will be urged to consider carefully the increased risk that household-mixing poses, after the prime minister described this Christmas as a “season to be jolly careful”.
The rules also mean that, if parents have three children living elsewhere in different homes, they will not all be able to gather for Christmas.
There will be no lifting of restrictions for the new year period, by which time areas of England will have returned to the three-tier system that will kick in when the lockdown ends next week.
Children of divorced parents will be able to move between Christmas “bubbles” so they can see both parents, as support bubbles count as a single household for the period.
And people will be allowed an extra day each side of the exemption period to travel to and from Northern Ireland to reflect the greater difficulties in doing so.
Guidance on festive activities – such as whether carol singing will be allowed – is expected to follow shortly.
Underlining her nervousness, Ms Sturgeon said: “I know everyone has a desire to see loved ones over the festive period.
“However, there is also a very real and legitimate anxiety that doing so could put those we love at risk, set back our progress as a country and result in unnecessary deaths and suffering.”
Those worries were “especially acute when we know we might be within weeks of being able to vaccinate a significant proportion of the population”, the first minister added.
Mark Drakeford, the Welsh first minister, echoed the fear, admitting: “It will lead to more spreading of coronavirus because coronavirus thrives when people get together and the more people get together, the more coronavirus there will be.”
Following the four-nation meeting, Michael Gove, the Cabinet Office minister, said: “The UK-wide agreement reached today will offer hope for families and friends who have made many sacrifices over this difficult year.
“We have listened to scientific and clinical advice on how best to minimise the risk and reach a balanced and workable set of rules that we hope will allow people to spend time together at this important time of year.”
And an official statement released by the four ministers stated: “This cannot be a ‘normal’ Christmas.
“But, as we approach the festive period, we have been working closely together to find a way for family and friends to see each other, even if it is for a short time – and recognising that it must be both limited and cautious.”
It is possible that the definition of a household might be different in Scotland, after Ms Sturgeon pointed to potential differences.