Ambulance services have been accused of not doing enough to meet government targets for responding to 999 calls.

The magazine Health Which? says response times in all but one region in England are still too long, despite the introduction of a new system for deciding which 999 calls are the most urgent.

But health officials insist ambulance services are improving despite the publicity.

Click here to see how your ambulance trust performed

Three years ago ambulances were given targets for response times, the aim being to reach the majority of emergencies in eight minutes by 2001.

But, although only a handful of ambulance services are hitting "call prioritisation" targets, the Department of Health argues that new money will mean continued improvements.

Latest official figures showed that Staffordshire ambulance service was the only one in England to exceed the target of reaching 75% of life-threatening "category A" calls in the target time.

But the Department of Health says that since the figures were published in June, a further three ambulance trusts are now achieving the response times.

London service worst

London Ambulance Service (LAS) reported the worst response times, reaching only 36% of emergencies in eight minutes.

But LAS chief executive, Peter Bradley told Health Which? that new systems and new money are needed to turn things around.

It is easy to knock London's performance but we have unique problems

Peter Bradley London Ambulance Service

"It is easy to knock London's performance but we have unique problems," he said.

Richard Diment, a spokesman for the Ambulance Service Association, said: "It's using figures that are six months out of date. They are basing the report on where we were on March 31 2000.

"The target date we were given is March 31 2001, so it is during this current year that quite dramatic changes are taking place.

"The report is unnecessarily alarmist. About six services are now consistently reaching the target, including Warwickshire, Mersey Regional and Lancashire.

"And probably most of them will have reached the target by the target date."

All ambulance services are expected to have call prioritisation systems in place by next year.

This allows emergencies such as heart attacks to be prioritised over situations which are not life-threatening, rather than treating all 999 calls the same.

Nationally, achieving the eight minute response time for category A calls would save at least 3,000 heart attack victims a year.

Additional funding

An additional �21m was allocated earlier this year to help ambulance trusts achieve the faster response times.

"Getting 999 emergency ambulance to patients in time to make a real difference is a key priority for the government," a Department of Health spokeswoman said.

But Health Which?'s report suggests the prioritisation system itself can cause problems.

For example, some ambulance services do not prioritise patients who are paralysed or a woman about to give birth.

Yet, if too many conditions are prioritised, managers argue that the service is spread too thinly and response times can not be reached.

The number of emergency calls rose by 7% to 4.1 million last year.