Senior NHS negotiators have been drafted in to help resolve a dispute between ambulance leaders and local health chiefs amid a rising number of 999 callers.

The East of England Ambulance NHS Foundation Trust (EEAST) says it can prove that the increase in demand from patients is fast out-stripping funding from the region's clinical commissioning groups (CCGs), which controls the local NHS budget.

But the CCGs have been reluctant to plug that financial gap - leading to negotiators at national level being called in.

The east of England CCGs themselves are tasked with making combined savings of more than £100m.

It comes less than two months after EEAST had its busiest ever day on December 27, when it treated more than 4,000 patients.

The trust is currently missing emergency response targets, as are all ambulance trusts across England, and 999 calls in December were up by 16pc compared to December 2015.

In his latest update to the trust's board EEAST chief executive Robert Morton said the dispute over funding meant the trust is unable to fully plan its spending and saving targets over the next two years.

Today the CCGs confirmed a deal had been struck for 2017/18, but no deal has yet been agreed for 2018/19.

A spokesman for the ambulance trust said: 'While good progress has been made, everyone involved is continuing to address any outstanding issues that will enable the parties to finalise a contract.

'We understand that a number of ambulance trust 999 contracts have been subject to the NHS contract dispute resolution process so like many of the matters we work on with our CCG partners, this is a national picture.'

A spokesman for Ipswich and East Suffolk CCG, the lead commissioner for ambulances in the east of England, added: 'The CCGs continue to work with EEAST to ensure the best possible outcomes for patients.'

Ambulance trust set for £10m deficit

Too much spending on private ambulance services and agency staff are among the key reasons why EEAST is set to end this financial year in the red for the first time in a number of years.

The ambulance trust is currently set for a £10.6m deficit, despite starting the year by predicting to finish with a surplus.

It has overspent its budget on private ambulance services by more than £10m while £1.9m has been spent on agency staff.

The trust agreed to spend more money than planned on private ambulances in order to respond faster to patients waiting for medical help, but only some of this cash is being provided by the clinical commissioning groups.

Robert Morton, the trust's chief executive, last month told the BBC he wanted more money for the ambulance trust and he wanted it 'now'.

The trust is also behind its plan to deliver its savings target of £6.7m.

It has saved £4.1m so far this financial year.