The chances of the final easing of lockdown restrictions in England taking place on 21 June are “close to nil”, according to reports.
The decision on whether to proceed with the planned roadmap out of lockdown - which would see a series of restrictions lifted in late June - could be delayed until the full extent of the spread of Indian variant is known.
The effectiveness of the vaccines against the strain of the virus and its transmissibility will also be factors in determining whether to continue as planned.
A spike in cases of the variant has been seen in recent weeks across the UK.
‘Some easing we’ve done today will have to be reversed’
The government adviser said: “It is clear some social distancing will have to be retained, not everything we've set out for 21 June is likely to happen.
"But it is also possible some of the easing we've done today will have to be reversed."
More than 2,000 people have Indian variant in UK
The report comes after Health Secretary Matt Hancock told the House of Commons that more than 2,000 people in the UK have confirmed cases of the Indian variant.
Surge testing and vaccination is underway in the areas of the North West of England, where the strain is most common, with 483 cases in Bolton and Blackburn with Darwen.
Matt Hancock told MPs that while the Indian variant does seem to be more transmissible, “early data” suggests that existing vaccines are effective against it.
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