Six hospitals have issued a joint warning for people to stay away from emergency departments except for in "genuine, life-threatening situations", after a surge in numbers left some patients waiting for up to 12 hours.
Hospital trusts across West Yorkshire and Harrogate in North Yorkshire said the current pressures have left them with no choice but to prioritise patients presenting with acute illness or injuries. The area covers more than 2.5 million people.
Last month, they released a statement saying Covid patients are still placing 'significant strain' on their hospitals.
West Yorkshire Association of Acute Trusts said its most recent emergency department figures show a 14.2% increase in attendance compared with the same week last year.
Dr Andrew Lockey, emergency medicine consultant with Calderdale and Huddersfield NHS Foundation Trust, said: "It's really important that people only come to an accident and emergency department if they really need to.
"Our hospitals are extremely busy, and people are having to wait a long time to be seen.
"Over the past two weeks we've faced huge challenges with the sharp uplift in the number of people attending accident and emergency.
"This places additional pressure on our teams who are responsible for treating patients with serious and life-threatening conditions.
"If you are unwell and are unsure which healthcare service you need, call NHS 111. A highly trained clinical adviser will direct you to the most appropriate service."
Responding to warnings issued today by six hospitals in West Yorkshire and a critical incident declared by South Central Ambulance Service, Saffron Cordery, deputy chief executive of NHS Providers, said “NHS trusts right across England are still under enormous strain as the number of people with COVID-19 in hospital continues to rise.
“Although thanks to mass vaccination we’re not seeing the high levels of serious illness and deaths we’ve seen before, COVID-19 hasn’t gone away.
“We’re very concerned about the real pressures across the whole health and care system. A very high number of hospital beds are occupied and combined with staff absences and severe workforce shortages this means that trusts can’t recover care backlogs as quickly as they want to.
“Ambulance services are doing everything they can in these extremely difficult circumstances but the extra pressures are leading to growing delays to handovers to busy emergency departments. This means that ambulances aren’t able to get back out into the community as quickly as they would like.
“Trust leaders and everybody in the NHS are keenly aware of the impact of delays and addressing them is an absolute priority.”
It comes as a health board in Wales asked patients to only attend one of its hospitals in life-threatening cases.
Aneurin Bevan University Health Board has said its services are under "under sustained and unprecedented pressure".
A spokesperson said the Grange University Hospital in Cwmbran is seeing "a record number of attendances" and that non-life-threatening patients were waiting more than 14 hours to see a doctor.
A statement yesterday read: "The health board is under sustained and unprecedented pressure. Despite actions to try to stabilise our services today we have had to declare a state of ‘business continuity’.
"Our emergency department at the Grange University Hospital is extremely busy, and we have seen a record number of attendances, and waits to see a doctor, in some cases, are greater than 14 hours where the patient’s condition isn’t life threatening.
"We have very few beds available across our hospitals to accommodate patients requiring admission.
Meanwhile, Northern Ireland's hospital trusts have issued a public warning.
Hospital bosses say coronavirus is continuing to 'exacerbate' pressures.
Patients are now facing waits of up to 60 hours in emergency departments to be moved to a bed on a ward.
