Government 'aware of issues' at Royal Cornwall Hospital
The prime minister has said the government is aware of issues at a hospital which is struggling to cope with "extreme pressure" on services.
Medics have been asked to step in to help after the Royal Cornwall Hospital declared a "critical incident".
Truro and Falmouth MP Sarah Newton said the situation was "extremely worrying for all families across Cornwall who rely on" the hospital.
Theresa May told the House of Commons she was "aware of issues".
On Monday 15 ambulances were queued up outside the hospital near Truro.
Mrs May was responding to a Commons question from Mrs Newton, who will meet with Health Secretary Matt Hancock later to discuss the matter.
Royal Cornwall Hospital Trust chief executive Kate Shields said: "We reached the point where we couldn't take any more people into the hospital because the long corridor was full of people and we couldn't get people off ambulances."
The hospital has seen increased pressure on services since April, but Mrs Shields admitted "we don't really know why".
'Distressing for staff'
She said it was the first critical incident to be declared at the hospital for 14 months and she expected it to last until Thursday.
By declaring a critical incident hospital bosses can work with other partners including Cornwall Council, the Cornwall Partnership Trust, the South Western Ambulance Trust and NHS 111 to relieving pressure on services.
Doctors have also been brought in from outside the hospital to review patients who may be able to be discharged.
Centres have been established at smaller hospitals in west Cornwall and Redruth for patients who may not require treatment at the emergency department, but are too serious for minor injuries units.
In addition GPs have been asked to visit community hospitals and care homes to help alleviate the pressure.
As a result some routine appointments at GP surgeries have been cancelled.
Mrs Shields said the situation was "distressing" for staff.