A scientist advising the government on the UK’s response to the Chinese coronavirus has predicted that a “substantial third wave” is coming. Meanwhile, the prime minister is set to announce a four-week delay to the end of restrictions.

Speaking to the BBC’s Andrew Marr on Sunday, Professor Andrew Hayward of the Scientific Advisory Group on Emergencies (SAGE) said: “I think it’s now very clear that we will have a substantial third wave of infections.

“The really big question is how much that wave of infections is going to translate into hospitalisations. The fact that we’ve got 55 per cent of the adult population double vaccinated means that this would be substantially less than it could have been. But we still don’t know exactly how bad it would be.”

Asked if he thought there was any chance that the UK would lift all restrictions as Prime Minister Boris Johnson had planned by June 21st, Professor Hayward said: “I think if we were to open up more, that would just really fan the flames and lead to this increasing even faster…

“I think we’ve got to be really cautious because there is a substantial chance we could have a wave of hospitalisations that could put very substantial pressure on the NHS at a time that it’s really trying to deal with the enormous backlog of cases of people waiting for hospital care.”

The University College London epidemiologist’s remarks come amidst several reports in the media on Monday that Prime Minister Johnson is set to announce this evening a delay to the end of restrictions. Sky News, The Times, and The Telegraph report government sources as saying that ‘Freedom Day’ will now take place on July 19th with a review after a fortnight. Several Cabinet ministers, the UK’s scientific advisor, and England’s chief medical officer agreed to the move, according to reports.

Measures remaining in place include many sectors of hospitality remaining closed or under restrictions, limits on gatherings, and continued mask-wearing in indoor public settings like shops, while recommendations on working from home where possible will be maintained.

A senior government source told The Telegraph: “The message has always been cautious but irreversible. That has been our mantra throughout and that continues.

“It would be far worse to have uncertainty and go backwards. It is better to be cautious and have certainty. It is one last heave. It is a straight race between the vaccine and the virus.”

Downing Street’s rationale for continuing the restrictions is reportedly so that the country can monitor the development of the Indian strain of COVID-19, which is said to be 60 per cent more infectious and more likely to put people in hospital.

Professor Hayward had said on The Andrew Marr Show: “Sixty per cent more infectious is extremely worrying. That’s the main thing that would drive the speed with which the next wave comes along.

“And the fact that the level of hospitalisations from this infection appears to be maybe up to double those from the previous infection is of course also extremely concerning, even in the context of people having had a single dose of vaccine.”

On Monday, Health Minister Edward Argar conceded that it was “possible” that had India been added to the red list of travel destinations sooner, it was “possible” that it might have prevented the coming delay to lifting restrictions. India had been put on the red list two weeks after neighbouring Pakistan and Bangladesh, despite concerns about a new variant.

Speaking to Sky News, Mr Argar said the suggestion was “hypothetical”, adding: “I don’t think that would have necessarily stopped the variant coming.”

However, when pressed, he admitted: “It’s a hypothetical. It’s possible, but there’s no way of knowing that.”

Last month, it was reported that around 20,000 people travelling from India entered the UK in the first three weeks of April when concerns were being raised about the strain, while another report from May estimated that some 100 aeroplanes had landed at British airports from India, after travel restrictions had been imposed.