A man in the US with no travel history has tested positive for the new mutated strain of coronavirus which was first found in the UK.
The man lives in Colorado and the news was announced on Tuesday evening by the state's Governor Jared Polis.
He tweeted an official statement which reads: "Today we discovered Colorado’s first case of the COVID-19 variant B.1.1.7, the same variant discovered in the UK.
"The health and safety of Coloradans is our top priority and we will monitor this case, as well as all COVID-19 indicators, very closely."
The news comes after scientists have warned that the mutated coronavirus strain could cause a higher mortality rate next year than the original variant.
Researchers at the London School of Hygiene and Tropical Medicine said the increase in transmissibility of the new Covid-19 could see more people being hospitalised and eventually dying after contracting the virus.
A report - which is still preliminary and has not been peer reviewed yet - has shown that, unless more restrictions are in place, up to 118,000 people could die of Covid-19 by the summer in a worst case scenario.
But a more likely scenario, with 200,000 being vaccinated every week, would see 83,300 people dying by the end of June.
Scientists have said that the current average of 200,000 jabs being administered every week "does not have much impact".
However, if that number goes up to two million jabs every week, it could lead to a significant decrease in the number of new infections and deaths.
But a group of scientists has warned that England is entering its worst moment of the Covid-19 crisis and should immediately be plunged into a third national lockdown.
Independent Sage - set up as an alternative to the Government’s own Sage committee of advisers - said tougher restrictions are necessary because England's Tier 4 rules have shown no sign of controlling the variant which is up to 70% more transmissible.
Boris Johnson was holding crisis talks on Tuesday night, and Health Secretary Matt Hancock is due to announce any changes to tier areas in a statement to the Commons on Wednesday.
