Hospitals will suffer an "inevitable" crisis of bed shortages when the winter flu season strikes, doctors warn.

The Intensive Care Society (ICS) said only 2.5 per cent of hospital beds were allocated for critical care in the UK, the lowest level in Europe.

This compares to 3.5 per cent in France and Germany and four per cent in Denmark.

The UK also has on average the smallest sized intensive care units - six beds per unit compared to 19 per unit in Belgium.

At the moment hospitals in Sussex are managing to cope with demand but will face major problems if there is a serious flu outbreak.

There are 14 intensive care beds at the busiest hospital in Sussex, the Royal Sussex County Hospital in Brighton. Two more beds are due to open next year and there are another eight in its cardiac department.

A Royal Sussex County spokesman said: "There are no signs of major problems with flu at the moment. We are starting to see an increase in the number of patients with chest problems coming into the hospital but the units have not been affected.

"Winter is always a busy time but we hope we have made enough preparations to cope."

ICS president Saxon Ridley said many beds were taken up with patients who needed intensive care after major planned surgery, leaving emergency patients without a bed.

He said hospitals were keen not to cancel operations in their efforts to cut waiting lists so surgery went ahead regardless of the need to have beds available for emergency cases, which made up 75 per cent of intensive care workload.

Dr Ridley said: "The number of transfers is increasing and an intensive care bed crisis this winter is inevitable. Hospitals are creaking because there are so many patients at every level."

Health Secretary John Reid said there was no evidence in the report to suggest patients would receive inadequate critical care.

He said: "It is irresponsible for the ICS to use an informal canvass of some members opinions in order to worry the public and patients without reason.

"Capacity for critical care is at record levels with 3,128 beds, a 32 per cent increase since January 2000."