A nurse was filmed telling patients in a hospital waiting room they may have to wait up to 13 hours to be seen by a doctor, adding there were no available beds.
The woman was addressing a crowd in Harlow A&E, which is run by Princess Alexandra Hospital Trust in Essex on Monday evening.
Health Secretary Sajid Javid was shown the clip on BBC Breakfast this morning where the nurse also asked relatives to leave due to space constraints.
She was heard saying: "We've currently got 170 patients in the department, there are 90 patients waiting to be seen at the moment.
"Our current wait time for a doctor is seven and a half hours.
"I will estimate by the time I go home in the morning at 8 o'clock some of you will still be here waiting for a doctor because the waits will get up to 12 or 13 hours.
"There are currently no beds in the trust. We're trying to make more space if we can but if people are admitted there's a chance they'll stay in A&E overnight.
"We will do our best to make you comfortable, we will do our best to look after you, but please don't expect you will be going directly to a ward because that might not happen."
Mr Javid said the NHS is seeing "very high levels of demand" in the aftermath of the Covid-19 pandemic.
He said: "Of course, that's not a thing that anyone wants to see."
He added: "Because of the impact of Covid... we know already from our NHS estimates, we think some 11 to 13 million people stayed away from the NHS because of the pandemic.
"Many of those people are coming forward, many of those to A&E, and we're seeing very high levels of demand.
"That is a real challenge for the NHS across the system.
"What we're doing about it is investing record amounts including in ambulance trusts, the 111 calling service that now has more call handlers than ever before, we put in just last year additional emergency £400 million for A&E facilities across the country.
"So I think the NHS is doing everything it possibly can be doing.
"The waiting times are improving but it's not what anyone wants to see, those kinds of waits."
It comes as Shadow Health Secretary Wes Streeting backed wider use of private healthcare in the NHS.
The frontbencher believed sending NHS patients for private treatment could help slash delays and backlogs unleashed by the coronavirus pandemic.
He said the 74-year-old health service was “going through the biggest crisis in its history”.
Six million people are on a waiting list in England - one in nine of the population.
Mr Streeting told the Institute for Government think tank yesterday: “I think it is morally unacceptable that we now have in this country a two-tier health system where the number of people paying to go private has effectively doubled over the course of a decade, and against the backdrop of record high NHS waiting lists we have got a situation where those who can pay to jump the queue do and those who can’t are left behind.
“I’ve had some criticism, particularly from the left, who said this is ‘a privatisation agenda’ and ‘how could you reconcile using the private sector to bring down NHS waiting lists?’
“The answer is twofold - I don’t think the British people would buy an ideological argument that says because of our ideological principle you should be waiting longer; secondly, I do not think a situation where working-class people who can’t afford to pay private wait longer is a left-wing position.
“I think making sure you’re paying for people to get care as fast as possible within the NHS - whether that’s using the private sector or not - is a left-wing position.”
Stephanie Lawton, chief operating officer at The Princess Alexandra Hospital NHS Trust, said: "We are currently experiencing extremely high demand for our emergency care services and have seen a significant increase in attendances in our emergency department.
"Our teams are working hard to assess and treat patients as quickly and effectively as possible to reduce delays, prioritising those in most clinical need.
"The public can help us to ease pressures by using the NHS 111 service for healthcare advice in non-urgent cases. As ever, please continue to call 999 or attend the emergency department for urgent and life-threatening emergencies."