A public health professor has said scrapping social-distancing measures in time for Christmas is an “enthusiastic approach that is premature” as the infection rate is still too high.

The Prime Minister said on Friday he hoped to ease the one-metre social distancing rule by November at the earliest.

Speaking at a press briefing at Downing Street, Boris Johnson said: “What we’re saying is that we hope that by November at the earliest, if we can continue to make progress in our struggle against the virus, then it may conceivably be possible to move away from the social-distancing measures, from the one-metre rule and other things by that time.

“That is entirely conditional, as I say, on our ability to continue to keep the virus under control.”

He said he hoped to review outstanding restrictions and allow a more significant return to normality “possibly in time for Christmas”.

Linda Bauld, professor of public health at the University of Edinburgh, said the infection rate in the community is currently too high for this to happen.

She pointed to the Office for National Statistics (ONS) infection survey published on Friday, which shows there are around 1,700 new cases per day in England, the same amount as last week.

She said most countries around the world still had the one-metre rule as a minimum, with the exception of New Zealand and Vietnam.

Speaking to the PA news agency, Prof Bauld said: “The only way it would be possible to get rid of the one-metre rule is if, over several months, we don’t have any Covid cases around the country.

“It does seem strange to suggest we can remove all social distancing if the virus is still in the community even in small levels, and when people are flying in and out of the country.

“This is an enthusiastic approach that’s premature.”

Mr Johnson also pledged an extra £3 billion of funding for the NHS and to increase testing capacity to 500,000 tests per day by the end of October to prepare for a potential second spike in Covid-19 cases in the winter.

Prof Bauld said any suggestion by the Government to scrap social distancing by November contradicted its statements about planning for a potential second wave.

She said: “We might be in a better place in November but I am not optimistic.

“Those of us in the scientific community are worried about winter so why would they say this could happen at such a crucial period?”

“Seems to me this is about trying to have a normal Christmas,” she added.

“I hope we have zero cases but we are not there yet.”

Chief medical officer for England, Professor Chris Whitty, has previously warned that social-distancing measures will need to stay in place until the discovery of a vaccine or highly-effective drugs to reduce the virus’s severity.

Current guidance says people should try to keep two metres apart or one metre if they can take extra precautionary measures such as wearing face coverings, sitting side-by-side as opposed to face on, and washing hands frequently.