It is “reckless and dangerous” to wait until Boxing Day to bring more areas into Tier 4, an expert has warned.
Ministers will meet on Wednesday to decide if more parts of England should be put under the toughest lockdown restrictions amid fears over the spread of a new mutant strain of coronavirus.
Birmingham and parts of Sussex are some of the areas that could join London and most parts of the South East in the highest tier from 26 December.
But Dr Zubaida Haque, a member of the Independent Sage group of scientists, is worried that waiting until Boxing Day will be too late for some people.
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Dr Haque tweeted: “With covid cases doubling in the #tier2 areas around #tier4, and NHS hospitals in tier 4 areas approaching capacity, it feels reckless & dangerous to wait until Boxing Day to implement a #tier4lockdown in England/UK.
“Why are the government putting politics before people's lives?”
The new variant, which is said to be 70% more infectious than previous strains, has already spread around the UK, with cases also identified in Wales and Scotland.
Health chiefs in Cumbria have said the new strain is in the county and could be behind sharp increases in cases, while Lancashire’s director of public health said there was a “high likelihood” the new variant was there as well.
Labour leader Sir Keir Starmer has written to the prime minister to say his party would back any government moves to tighten restrictions if that is what scientists recommended.
Cabinet minister Robert Jenrick confirmed the government would make a decision on whether the current restrictions were appropriate.
Professor Neil Ferguson told the Commons Science and Technology Committee on Wednesday that stricter rules over Christmas could have a positive impact on curbing the spread of infections.
He said: "The critical question is what happens in January and the extent we want to make public health measures more uniform across the country if the new variant is everywhere."
On Monday, the UK's chief scientific adviser Sir Patrick Vallance said rules would "need to be increased in some places, in due course, not reduced".
Anyone in a Tier 4 area must not mix with people outside their household over Christmas.
Non-essential shops, gyms, cinemas, hairdressers and bowling alleys have also been forced to close.
People will also be restricted to meeting one other person from another household in an outdoor public space.
Exemptions to the “stay at home” message that applied in the November lockdown will also apply in the new Tier 4 – including support bubbles, childcare bubbles and children whose parents are separated.
People will be allowed to travel for education, for childcare and to go to work if they cannot work from home, and they will be permitted unlimited outdoor exercise.
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