Norfolk police have mapped out proposals to cut almost �25m from the force's annual �148m budget – promising they will minimise the impact on front-line policing.

The plans include cutting the number of safer neighbourhood teams in Norwich from seven to four but maintaining the number of teams elsewhere in the country.

Virtually all civilian functions, except police community support officers, will be shared between Norfolk and Suffolk police, and the two forces will continue to look at ways they can share key policing functions.

The major investigation team was the first department to be merged and other units including firearms and other protective services are to be combined. Other services such as custody officers will soon be combined and a review is under way into the possibility of a joint control room to answer 999 calls.

Between 150 and 350 police officer posts will be lost over the next four years as the force looks to balance the books in the wake of government spending cuts. The exact number will be reviewed as the full scale of other savings becomes clear but the force hopes the number will be at the lower end of the scale. About 60 PCSO and 230 civilian posts will also go.

Chiefs say the plan is designed to protect the frontline as much as possible. For example, the reduction in safer neighbourhood teams in Norwich will see supervisory posts, inspector and sergeant ranks cut, but PCs and PCSOs on the ground will remain at current levels.

Other changes include reducing the demand on frontline officers by allowing PCSOs to deal with low level crime and anti-social behaviour, while non-crime incidents will be handled over the phone within the force's command and control room.

The new model will potentially lead to the loss of one superintendent, two chief inspectors, six inspectors and 20 sergeants, amounting to a predicted saving of about �1.7m.

The review is just one key element of the force's Challenge Programme – an umbrella title for a series of reviews looking into ways of cutting costs across its operations.

Chief constable Phil Gormley said the review should have minimal impact on local communities: 'We felt it was a priority to retain the principles of neighbourhood policing, not least because the SNTs are working well and are embedded within communities.'

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