NHS England emergency-care director Prof Julian Redhead said: "The twin pressures of winter viruses and problems discharging patients means hospitals are close to full – even as more beds have been opened to manage the increased demand.
"While pressures on hospitals remains incredibly high, it's vital people continue to use NHS services in the normal way – using 111 and 111 online if you need advice and support for health conditions, and only using 999 or attending A&E in life-threatening emergencies."
The rising pressures on hospitals have led to reports of patients facing long delays in A&E and ambulance queuing outside.
Last month the Royal College of Nursing warned lives were being put at risk by what they called corridor care with patients having to be treated in makeshift areas including car parks, cupboards and nursing stations.
Saffron Cordery, of NHS Providers, which represents hospitals, said it has been a difficult few months.
"It's worrying that we are seeing record-breaking pressure despite the tireless efforts of trust leaders and frontline teams who are doing their level best to provide high quality care and to see patients as quickly as possible in very challenging circumstances."