Pressure is growing for the toughest coronavirus restrictions to be expanded across the country in the face of increasing strain on hospitals in England where the number of Covid-19 patients is at its highest ever level during the pandemic.

Health Secretary Matt Hancock is due to announce any changes to tier areas in a statement to the Commons on Wednesday.

With case rates rising in all regions of England, and record patient numbers, any changes are likely to involve areas moving up a tier rather than down.

Figures from NHS England showed there were 21,787 patients in NHS hospitals in England as of 8am on Tuesday, compared with 20,426 on Monday, and 18,974 at the first wave peak on April 12.

Trusts in England were told in a letter just before Christmas to begin planning for the use of Nightingale hospitals, although concerns have been raised around staffing the sites.

Five of the seven NHS regions in England are currently reporting a record number of Covid-19 hospital patients: Eastern England, London, the Midlands, south-east England and south-west England.

The other two regions, north-east and north-west England, remain below peak levels that were set in mid-November.

One senior doctor said some trusts in London and the South East are considering the option of setting up tents outside hospitals – something normally reserved for sudden events such as terror attacks or industrial disasters – to triage patients.

Emergency medicine consultant Simon Walsh said staff are working in “major incident mode” and called on the Government to set out a “coherent plan” to get through the coming weeks.

Dr Walsh, who is also deputy chairman of the British Medical Association’s UK consultants committee told the PA news agency: “(Trusts are) having crisis meetings, they’re calling on staff to come in to work if they’re able to on their days off.

“They are dealing with queues of ambulances outside many emergency departments, often with patients sat in the ambulances for many hours until they can be offloaded into the department because there simply isn’t any space to put them in.”

His remarks came as coronavirus patients at a hospital in Romford were forced to be treated outside in ambulances before entering the building due to the rising numbers of cases.

Footage shared on social media of Queen’s Hospital in Romford appeared to show dozens of emergency vehicles queueing outside the hospital.

A statement released by the Barking, Havering and Redbridge University Hospitals NHS Trust, which runs the hospital, urged people to only contact ambulance services in the case of real emergencies.

Total coronavirus cases hit a new record on Tuesday, rising above 50,000 cases for the first time, to 53,135 lab-confirmed cases.

While the number is likely to have been inflated by a delay in the reporting of data across the UK over Christmas – with some of the total including people who tested positive before December 25 – Dr Susan Hopkins said the figures are “largely a reflection of a real increase.”

The senior medical adviser for Public Health England, said the “unprecedented levels” of Covid-19 infection across the UK was of “extreme concern”.

It is not possible to make direct comparisons with the level of infection during the first wave of the virus, because mass testing was only introduced in the UK in May, but it has been estimated there may have been as many 100,000 cases a day at the peak in late March and early April.

An expert adviser to the Government said national coronavirus restrictions are needed to prevent a “catastrophe” amid rising infections, and the head of an organisation representing health trusts said “as much of the country as possible” should go into the harshest Tier 4.

Professor Andrew Hayward, of the Government’s New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), said widespread Tier 4 restrictions – or even higher – are likely to be needed as the country moves towards “near-lockdown”.

He told BBC Radio 4’s Today programme: “I think we are entering a very dangerous new phase of the pandemic and we’re going to need decisive, early, national action to prevent a catastrophe in January and February.”

Asked whether a national Tier 4 lockdown should be brought in, NHS Providers deputy chief executive Saffron Cordery told BBC Radio Five Live: “I think we need to see, yes, as much of the country as possible in Tier 4.”

She said some trusts are reporting up to three times the number of Covid-19 patients as at the peak of the first wave.

I think we are entering a very dangerous new phase of the pandemic and we’re going to need decisive, early, national action to prevent a catastrophe in January and February

Fears around the effects of reopening schools on overall case numbers have also led to calls from scientists and school leaders suggesting a delay might be needed.

The Government said it is “still planning for a staggered opening of schools” but is keeping the approach under constant review,

Prof Hayward, professor of infectious diseases epidemiology at University College London, said he thinks schools will have to return “maybe a little bit later” and reopening would mean “we’re going to have to have increased, strict restrictions in other areas of society to pay for that”.

Fellow Nervtag member Professor Neil Ferguson said there had been a “balancing act” since lockdown was initially eased to try to keep control of the virus while maintaining “some semblance of normal society” but that the new variant had made it more difficult.

He told BBC Radio 4’s World At One programme: “Clearly nobody wants to keep schools shut. But if that’s the only alternative to having exponentially growing numbers of hospitalisations, that may be required at least for a period.”

Geoff Barton, general secretary of the Association of School and College Leaders (ASCL), welcomed the Government’s plans for soldiers to offer remote support for testing in schools, but warned it is unlikely to be enough.

On Tuesday, 91-year-old grandmother Margaret Keenan, who became the first person in the world to receive the Pfizer vaccine earlier this month following its clinical approval, was given her second dose at Coventry’s University Hospital.

Hopes are high for the approval of the Oxford/AstraZeneca jab, reportedly expected imminently by the Medicines and Healthcare products Regulatory Agency.

More than six million people in east and south-east England went into the highest level of restrictions on Saturday, meaning 24 million – 43% of the population – are now affected.

Lockdown measures are also in place across the other three home nations, after mainland Scotland entered Level 4 restrictions from Saturday for three weeks, and a similar stay-at-home order is in place in Wales.

Northern Ireland has also entered a new six-week lockdown, and the first-week measures are the toughest yet, with a form of curfew in operation from 8pm, shops closed from that time and all indoor and outdoor gatherings prohibited until 6am.