On Saturday, First Minister Nicola Sturgeon announced that the UK-wide easing of coronavirus restrictions between December 23-27 would not go ahead in Scotland with people urged to only use the flexibility on Christmas Day if they “really, truly need to”.

This followed a similar move from England, and Wales cancelled the easing altogether.

Sturgeon said yesterday that the speed at which it could spread meant this was "probably the most serious and potentially dangerous juncture we have faced" in the pandemic. But, she said Scotland still had the opportunity to act on a preventative basis.

These tougher measures are being introduced to account for the new Covid-19 variant becoming the dominant coronavirus strain in many parts of the UK.

READ MORE: Scottish mainland to move to Level 4 restrictions from 26 December

Where did it come from?

The new variant was initially detected in south-east England with UK Health Secretary Matt Hancock telling MPs earlier this week that there had been cases reported in nearly 60 local authority areas.

By December, it has been reported that more than 60% of infections in London had been confirmed with the capital and areas like Kent and Essex in new Tier 4 restrictions.

It has also been linked to the rapid rise of cases in Wales with the country's health minister Vaughan Gething telling BBC News on Sunday that it was "effectively seeded" across the country with "large concentrations in the south of Wales but also north-east Wales has been particularly affected".

So far in Scotland, a total of 17 cases have been reported but it is currently unclear how widely it is circulating with the First Minister saying this is "likely to be an understatement of its true prevalence right now".

There is also "concern" that this strain may be driving what appears to be faster transmission of Covid in some hospitals and care homes.

​READ MORE: All UK should follow Scottish model in Covid variant fight, Devi Sridhar says

Is it more deadly and dangerous?

While the spread of the new variant is much faster than before and therefore harder to control, there is currently no suggestion that it is more deadly or causes more severe symptoms.

Early data, subject to review, suggests that it may be up to 70% more transmissible than the earlier variant and experts believe it could increase the R number - or reproductive rate of the virus - by 0.4 or more.

Testing for the new variant remains the same and the clinical outcome is no different.

There is also nothing to suggest that long-awaited vaccines being rolled out across the UK would no longer work with the new strain.

The NHS also confirmed the new strain produces the same symptoms, meaning people will still experience a high temperature, a persistent cough, a loss of taste and smell or any combination of all the above.

​READ MORE: Warnings of testing data error as Scotland records three more Covid deaths

How are nations reacting? 

In Scotland, Christmas Day will be the only time restrictions are eased but people are being urged to take advantage only if absolutely necessary.

A ban on travel between Scotland and other parts of the UK, except for essential purposes.

Police patrols across the Border with England are to be doubled but there are no plans for checkpoints or roadblocks with Police Scotland's Chief Constable Iain Livingstone saying they were not "appropriate" or "proportionate". 

The whole of Scotland will be moving to level 4 or level 3 from Boxing Day.

All of mainland Scotland will be moved into level 4 restrictions - which mean the closure of non-essential shops, pubs, restaurants and gyms - for three weeks.

Orkney, Shetland, the Western Isles and other island communities will be placed into level 3.

In England, areas in the south-east and London have now moved into a new Tier 4 of restrictions, which is effectively a localised lockdown.

The easing of restrictions at Christmas has also been cut to just Christmas Day for areas in Tiers 1 to 3 but has been scrapped for those now in Tier 4.

In Wales, First Minister Mark Drakeford announced an immediate lockdown for the country yesterday which came into effect today.

Wales was due to move to the highest level available, from December 28, with non-essential retail, close contact services, gyms and leisure centres and hospitality due to close over Christmas Eve and Christmas Day, but Mr Drakeford said it would do so at end of trading on Saturday.

Northern Ireland will have a six-week lockdown from Boxing Day with stricter restrictions - including essential shops closing at 8pm and no sport - for the first week, until January 2.

Christmas bubbles in NI have a window of 22 to 28 December, but the days at each end are for travelling into or out of the nation.