Hospital chiefs have strenuously denied an MP’s claims that ambulances are kept waiting outside A&E to help meet Government targets.

Dan Poulter said ambulances are kept stacked outside the A&E department because the clock on waiting time targets does not start ticking until patients have been admitted.

Although the coalition Government scrapped Labour’s four-hour A&E target last year, management are expected to investigate if more than 5 per cent of patients wait more than four hours to be treated.

Ipswich Hospital has hit back at Dr Poulter’s claims saying it would never not offload a patient from an emergency ambulance to meet a target.

The row comes as the hospital admitted on Wednesday it saw a 50 per cent hike on the number of emergency ambulances, compared with an average weekday.

A spokeswoman for the hospital said there were delays of around an hour in handing over patients because the sheer number of those requiring assessment at the same time.

Dr Poulter, MP for North Ipswich and Central Suffolk, said his office was investigating concerns the healthcare infrastructure could not cope during busy times.

“The reason ambulances stack is because they don’t count as part of the four-hour waiting times in A&E,” said Dr Poulter, a consultant gynaecologist.

“I would be hugely concerned if the hospital – because A&E are busy – are using this to distort the figures because people in ambulances need to be treated and need to be treated quickly.”

Dr Poulter, who said he had heard anecdotal evidence about this practice from talking to doctors and nurses, added: “Usually there’s some kind of prioritising but if you are in an ambulance and coming to hospital we need some fairly quick treatment, so it’s not good for patients.

“Sometimes you do have periods when there’s a particular incident or a busy time.

“Of course every hospital has a couple of busy days but nevertheless my main concern if we have got ambulances stacked up outside A&E is that it is to the detriment of patients.”

Dr Tony Nicholl, Ipswich Hospital’s clinical chair for general and acute services, including A&E, said: “Under no circumstances, at any time, would we ever not offload a patient from an emergency ambulance to meet a target.

“It is very disappointing that Dr Poulter could suggest this and I will be asking for an urgent meeting with him to discuss his comment.”