North Norfolk is the worst area in the region for ambulance response times to patients suffering strokes and cardiac arrests.
The damning fact is revealed in a new report, which calls for another 64 front line staff in the district.
Ambulance chiefs are tomorrow due to answer the hard hitting points made in the clinical capacity review.
North Norfolk MP and health minister Norman Lamb welcomed a raft of recommendations, but called on the trust to act.
'They have made promises they did not keep in the past. They said 15 extra ambulances were being brought into the system earlier this year and north Norfolk was getting an extra 24/7 ambulance, which would be initially staffed on over-time. However, it has been taken away after ten shifts. It is not good and undermines people's trust in the ambulance service.'
'It reinforces the impetus to get the chief executive position sorted out and I am putting pressure on nationally to get that resolved. We need leadership to drive change. They need to strip out layers of management to invest in the front line and they need to get on with that,' he said.
The report reveals that the organisation will need more than 400 extra frontline staff over the next four years to meet demand.
The East of England Ambulance Service has been criticised by MPs this year for slow responses and has been ordered to improve by the health regulator, the Care Quality Commission.
The results of the NHS trust's clinical capacity review, carried out by a specialist emergency services consultancy, commissioned by the ambulance service, says that the organisation had a 'significant resource requirement' for 2014/15 to meet national targets and commissioner standards.
Under projections in the new review, the trust will still not respond to 75pc of the most urgent calls within eight minutes in north Norfolk, south Norfolk, west Norfolk, and west Suffolk in 2014/15.
Andrew Morgan, interim chief executive, pledged to hire 350 more frontline staff earlier this year of which 231 would be paramedics and specialist paramedics by the end of this financial year.
However, whilst the trust hired 44 qualified paramedics and three specialist paramedics in the first nine months of this year, figures earlier this month revealed that 40 paramedics left the NHS trust between January and September.
Board members of the ambulance trust, which is trying to recruit more paramedics, will set out their response to the review at a public meeting in Ipswich tomorrow.
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