Scotland's First Minister Nicola Sturgeon said "firm preventative action" was needed after the emergence of a faster-spreading strain of coronavirus. "It had been planned to ease the rules between Dec. 23 and 27 — but that will now only apply on Christmas Day. A ban on travel to the rest of the UK will apply over the festive period," she said, according to a BBC report. Scotland's toughest level four rules will come into effect across mainland Scotland from Dec. 26. Until then, local authority areas are expected to remain under their current level of restrictions. Schools will return later than originally planned after the Christmas holidays. Sturgeon said they should resume from Jan.11, with learning taking place online until at least Jan. 18. The level four restrictions — which mean the closure of non-essential shops, pubs, restaurants and gyms — will last for three weeks. They will apply across Scotland, with the exception of Orkney, Shetland, the Western Isles and other island communities where restrictions have recently been reduced. These areas will be placed in level three. The first minister said decisive action was required because of a new strain of COVID-19, which public health officials believe could be 70% more transmissible than previous strains. The new variant was first seen in mid-September in London and Kent — but by December it had become the "dominant variant" in London. Sturgeon said 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. So far 17 cases of the new strain had been identified in Scotland through genomic sequencing. "We do not yet know how widely this new strain of virus is circulating in Scotland, but I think we have to be realistic that that is likely to be an understatement of its true prevalence right now," she added. There was a "concern", however, that this strain may be driving what appears to be faster transmission of COVID in some hospitals and care homes. "Please believe me when I tell you... I would not be standing here on the Saturday before Christmas announcing this if I did not think this was necessary," Sturgeon added. Restrictions have also been tightened up over the Christmas period in England and Wales. The planned relaxation of the rules has been scrapped for large parts of southeast England, and cut to just Christmas Day for the rest of England and Wales. A fourth tier has also been created for some of the worst affected areas in England. The first minister said maintaining a "strict travel ban" would prevent more of the new strain entering Scotland from other parts of the UK, and reduce the risk of it spreading further within Scotland. This ban will remain in place throughout the festive period, meaning that cross-border travel will only be allowed for essential purposes. Sturgeon said she would be asking the police to consider how the enforcement of the ban could be strengthened. Indoor mixing will be allowed with one other household on Christmas day only, BBC reported The first minister says the travel restrictions will be the law. "They are not guidelines, they are law," she said. "The law will say that throughout this period it is not permitted to travel from Scotland to the rest of the UK or vice versa," she added. The first minister concluded her briefing by saying there was light at the end of the tunnel. The vaccination program is progressing at pace, she said. Scottish Conservative leader Douglas Ross said families "would be devastated" at the new measures so close to Christmas, according to Reuters. However, he added: "Given the rapidly increasing spread of the virus across the UK, and until our scientists know more about the transmission of this new variant, it is understandable why these restrictions are necessary at this time." "None of us want this, but these sacrifices will save lives," said Ross. The Scottish Liberal Democrat leader Willie Rennie has said schools that are set to open this week should close immediately. "When the science speaks in such stark terms, the leadership of the country must listen and act. "The new strain of the virus is already here and pupils and teachers who are infected in school next week could pass it onto vulnerable relatives on Christmas Day," he said. Richard Leonard, the leader of Labour north of the border, said the Scottish government needs to make decisions based on public health advice and "solid evidence". "To win public confidence behind this significant tightening of restrictions requires persuasive evidence to be published, transparency and openness, and a substantial rise in testing, otherwise not only will there be disappointment there will be a heightened risk of non-compliance," Leonard said. UK issues stricter measures amid new, more infectious strain of virus UK Prime Minister Boris Johnson has announced stricter virus restrictions ahead of Christmas amid a new, more infectious strain of coronavirus. He said that London and parts of southeast and east England will move to "Tier 4" restrictions with all non-essential shops closing from tomorrow. People in those areas must stay at home and cannot travel during the holidays and the government is recommending that people in all Tiers should stay local and not travel during Christmas. "It is with a very heavy heart I must tell you we cannot continue with Christmas as planned," Johnson said at a press conference on Saturday, stating that they "bitterly regret" the changes that need to be made. The government had originally planned to relax rules allowing three households to meet over five days for Christmas, but that will now be limited to just Christmas Day. It comes after a really "dramatic increase" in infections in the southeast and London where in some areas, most of the new COVID-19 cases are the new variant, said Professor Chris Whitty, England's chief medical officer. Whitty said that in other parts of England, this new variant was less present but that due to its transmissibility they were encouraging people not to travel. "The new variant contains 23 different changes," said Dr. Patrick Vallance, the UK's chief scientific officer, who described them as a "constellation of changes". Officials announced that the new strain was much more contagious due to these changes and up to 70% more transmissible. "We think it may be in other countries as well," added Vallance, according to a Euronews report. Wales First Minister Mark Drakeford said his nation would also lockdown from Sunday following a meeting with UK officials over the new variant. In Wales, people from two households can gather in a "bubble", Drakeford said. "The situation is incredibly serious. I cannot overstate this," he said. — Agencies