People over 50 and the clinically vulnerable will be offered their second dose of a Covid-19 vaccine eight weeks after the first in a bid to dampen any impact from the Indian variant of coronavirus.

Boris Johnson told a Downing Street press conference that second doses – which give people maximum protection against Covid-19 – will be brought forward from the planned 12-week interval to eight weeks.

He said there was no evidence that a rise in cases of the Indian variant was translating into unmanageable pressures on the NHS in terms of hospital admissions.

As a result, he said he believed there was no need to delay the road map reopening set for Monday, which will see people able to socialise indoors.

“But I have to level with you that this new variant could pose serious disruption to our progress and could make it more difficult to move to step four in June,” he said.

“I must stress that we will do whatever it takes to keep the public safe.”

Mr Johnson said that if the variant turned out to be much more transmissible than other variants, the country could face “hard choices”.