Patients waited too long in A&E at all but one of west London's hospital trusts during the last week of December.

Only Chelsea and Westminster Hospital hit the government's target by seeing and admitting, transferring or discharging at least 95 per cent of patients attending its emergency ward within four hours, figures published today reveal.

West Middlesex Hospital, in Isleworth, missed the target for the sixth week running, seeing just 91.4 per cent of patients in time during the week ending December 28.

The Hillingdon Hospitals saw 91.9 per cent of patients within four hours that week, falling shy of the target for a fifth week running.

The Imperial College trust, which runs five hospitals including Charing Cross in Hammersmith and St Mary's in Paddington, has now missed the target for 13 consecutive weeks after seeing just 90.8 per cent of patients in time during the Christmas week.

Across England the percentage of patients seen in time between October and December was 92.6 - the lowest quarterly result since the target was introduced at the end of 2004.

During the last week of December, nearly one in 10 patients (9.5 per cent) waited more than four hours in emergency wards nationwide.

However, that represents a slight increase on the previous week, during which just 88.8 per cent of patients were seen in time.

A spokesman for West Middlesex Hospital said: "The latest performance figures published show that despite a very busy winter period the majority of patients attending the hospital are treated, and either admitted or discharged all within four hours of first arriving at A&E. This target is a useful measure of performance but the provision of safe, high quality care is our priority for all our patients."

He added that the hospital had a 'robust' winter plan in place and worked closely with partner organisations, including the London Ambulance Service and other acute trusts, to ensure it maintained 'service resilience'.

"We have actively participated in on-going sector-wide discussions about making sure services are as resilient as they can be, and have supported actions taken as a result of those discussions. Over the past few years we have been making a number of improvements to emergency and unscheduled care at our hospital and this work is on-going," he said.

Dr Mark Porter, chairman of the British Medical Association Council said: "Patients should be treated on the basis of need, rather than arbitrary targets, but these figures show the NHS is under unprecedented levels of pressure.

"Staff are working flat out but the system is struggling to cope with the sheer number of patients coming through the door. Growing pressure on services throughout the year means hospitals have no spare capacity to deal with the winter spike in demand. So patients are enduring delays in their treatment, and the NHS finds itself running just to stand still."

He added that hospitals needed to stop prioritising targets so they could concentrate on improving the overall standard of care. He also said it was important to tackle the number of people attending A&E unnecessarily, by improving the advice line NHS 111.

Health secretary Jeremy Hunt told the BBC's Today programme this morning that the government was working to improve care outside hospitals for older patients with long-term conditions to reduce the strain on A&E departments.

He claimed the government had invested extra money in the NHS, adding 'we want to give hospitals every support to get them through a very difficult period'.