The chief constable of Norfolk has said there are 'no more big ticket items' to bring savings in its collaboration with Suffolk Constabulary.
It comes as a further £9m of savings need to be made in the force budget in the 2021/22 financial year in the wake of £32m of efficiency savings already cut from the budget.
At the police accountability forum on Monday, Norfolk's Chief Constable Simon Bailey said around £16m has already been cut from its budget by pooling resources with Suffolk.
He added 'the majority' of future savings would likely need to come from the Seven Force Collaboration with Essex, Cambridgeshire, Bedfordshire, Hertfordshire, Kent and Suffolk.
'Of £32m we have saved, 52pc has come from the collaboration with Suffolk,' said Mr Bailey.
'We have to accept there are no longer big ticket items to be addressed. We are of course always looking to improve our efficiency and effectiveness. While this year and next year we would appear to be in a position where the budget is not in deficit, savings are still being made consistently.
'We have to recognise, based on the current financial plan, we have £9m to find within the 2021/22 budget. I hope the majority of that will be driven through the force partnership and I want to do my best to protect the 2020 policing model.
'We can still squeeze but are we looking at millions of pounds of savings?
'I don't think that is within the bounds of what is acceptable to the two Police and Crime Commissioners.'
He added the 'potential for substantial savings' remains between the two forces. £1.8m could be saved across Norfolk and Suffolk Constabularies if all emergency calls were to be handled at a central control room, a move that has been rejected by Suffolk.
A previous report produced by a joint Norfolk and Suffolk team, which included assistant chief constables from both counties, said there was a clear business case for having the joint control room in Wymondham.
The report said the joint control room would save Norfolk £973,918 and Suffolk £870,567.
But Suffolk Police and Crime Commissioner Tim Passmore cut the plan short, saying he was 'unconvinced this would be in the public interest for both counties at this stage'.
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