Professor Whitty’s statement comes amid reports the Prime Minister could make changes to travel plans for Christmas bubbles today.
It is speculated the PM may order new travel restrictions for South East England in an attempt to stop it spreading to the rest of the country.
The UK reported 28,507 new COVID-19 cases on Friday and 489 deaths, with the “R” number estimated to be between 1.1 and 1.2.
SAGE is due to meet on Monday to discuss how the current three-tiered system of restrictions could be beefed up following the Christmas easing of the rules.
Professor Sir Mark Walport – a Sage member and a former chief scientific adviser to the Government – said there was a real possibility the new variant could have a “transmission advantage” enabling it to spread more rapidly.
He warned the country was heading into the new year in a “serious situation”, adding: “Scientists are working extremely hard to work out what is going on. But it does definitely seem possible that this (new strain) transmits more easily.
“Even in the parts of the country where the infection is coming under control the cases remain stubbornly high so the NHS is under great pressure.
“We are going into January in quite a serious situation where we do need quite strong measures to socially distance and if the virus is changing then that makes it even more imperative.”
And the Prime Minister is under growing pressure to further tighten coronavirus rules across England today.