The new mutated form of coronavirus has now spread to Wales and Scotland.
Experts analysing the genetic code of the variant say it is believed to have originated in South East England and was not imported from abroad.
Scientists contributing to the Government surveillance programme warn the VUI – 202012/01 variant appears to be spreading faster than other forms.
Their comments at a press briefing today suggested it has quickly spread the length and breadth of Britain.
The Covid-19 Genomics UK Consortium (COG-UK) experts said the genetic analysis does not suggest it causes more severe symptoms or can evade vaccines.
However it is sweeping the country quicker than the variant from Spain which was widespread during the first wave of the UK outbreak.
Prof Tom Connor, of Cardiff University, said: “In terms of in terms of geographic spread within the UK I mean, this virus spreads.
“It’s what it does and one of the reasons why we have lockdowns and why we have social distancing is because when people move around they you know you can take the virus with them.
He added: “It’s quite clear that it has spread beyond that and it is it is spreading into other parts of the country.”
COG-UK is a network of experts analysing genetic code from 140,000 Covid-19 patients based at 16 sites around the UK.
The network of experts said VUI – 202012/01 has caused concern because it is appearing most in areas of the country where infection rates are rising quickest.
They were also concerned because it displays 17 changes to the original virus – many more than previous variants detected by their surveillance.
Prof Nick Loman, of the Institute of Microbiology and Infection at Birmingham University, said: “It is a it is a quite a striking growth in that variant, much more than we would expect to see.
He added: “We don’t have any evidence that this has come from another country. It does sort of seem to come out of nowhere.
The Mirror reported today how one in ten Londoners who caught the novel coronavirus last month were infected with the new strain, according to an expert.
Dr Andrew Page, who is at the forefront of research work into Covid-19, has said the virus’s new strain “came out of nowhere”.
In the month since detection in October the mutated virus, which has been named VUI – 202012/01, has infected 19.2% of all new Covid-19 patients in Norfolk.
In London, 10% of patients had the new strain as of November, compared to 3% in Suffolk and 10% in Essex, Dr Page said.
While he urged people not to worry too much about the new variant and that the vaccine is thought to work against it, the scientist said the manner of its arrival was concerning.