Directors at the region's ambulance service were urged to get their books in order after it emerged that the trust had spent £3.3m more on private ambulance cover in the first quarter of 2013/14 than was previously planned.

Interim chairman Geoff Harris spoke of his concerns over the 'poorly planned' budget of the East of England Ambulance Service after it emerged that the NHS trust was so far in a £2.7m deficit for the financial year and aims to be in surplus of more than £3m by the end of the year.

Stephen Day, director of finance said there had been a net overspend of £1.7m on private ambulance contractors during April, May and June after taking into account a £1.6m underspend on ambulance staff pay.

He added that the trust was set to pay £700,000 in fines to commissioners for failing to hit response targets during the first quarter of the year. However, a financial recovery plan was under development, he said.

Mr Harris said the trust needed to sort its day-to-day accounts out quickly. 'We need to be more robust in future planning and we need to focus on expenditure and we need to get that sorted out. We need assurances that plans are in place and are going to deliver,' he said.

The warning comes as the East of England Ambulance Service is also looking to make £20m of savings to reinvest in front-line services.

Interim chief executive Andrew Morgan said the £20m was 'crucial' to the long-term sustainability of the organisation.