A total of 2,323 cases of the coronavirus variant first detected in India have been recorded in the UK, Health Secretary Matt Hancock said.
Speaking on Monday at the House of Commons, the lower house of British Parliament, Hancock said the variant is now the dominant strain of the virus in Bolton and Blackburn with Darwen, both in northwest England, with 483 confirmed cases, reports Xinhua news agency.
According to Hancock, in Bolton and Blackburn with Darwen, cases of the variant have doubled since last week.
"In Blackburn, hospitalisations are stable with eight people currently in hospital with Covid, and in Bolton 19 people are now in hospital with coronavirus, the majority of whom are eligible for a vaccine but haven't yet had a vaccine," he said.
"This shows the new variant is not tending to penetrate into older, vaccinated groups and it underlines again the importance of getting the jab especially, but not only amongst the vulnerable age groups."
Hancock has said there is a "high degree of confidence" that the current Covid vaccines will be effective against the India-related variant, but the virus could "spread like wildfire" among those who have not had a jab.
"While we also don't have the complete picture on the impact of the vaccine, the early laboratory data from Oxford University corroborates the evidence from Bolton Hospital and the initial observational data from India that vaccines are effective against this variant," he said.
Hancock's remarks came as the lockdown further eased on Monday across the UK despite concerns over risks posed by coronavirus variants, especially the Indian one.
From Monday, pubs, bars and restaurants in England were permitted to open indoors, while indoor entertainment resumed, including cinemas, museums and children's play areas.
Millions in England were allowed to meet outdoors in groups of up to 30 people, and meet indoors in groups of up to six or as two households.
More than 36.7 million people in Britain have been given the first jab of a coronavirus vaccine, according to the latest official figures.
The country's overall caseload and death toll stood at 4,468,570 and 127,946.