The BBC's June Kelly: "Reduced budgets have already changed the way police operate"
The bobby on the beat is becoming an "endangered species" in England and Wales because of government spending cuts, the Police Federation has said.
A survey for the organisation suggested 33 out of the 43 forces have scrapped, reduced or merged their neighbourhood policing teams since 2010.
Ministers called the funding settlement "challenging", but said forces had enough resources and crime was falling.
The home secretary is to address the federation's annual conference later.
In recent years, neighbourhood policing teams have been made up of police officers and police community support officers.
The federation - which represents rank and file officers - says officers were once able to build links with their local areas, but are now often only able to concentrate on responding to emergencies or carrying out pre-arranged visits to investigate crimes.
The survey suggests:
BBC home affairs correspondent Danny Shaw said the reform programme was still under way, but officers were keen to shift the focus to the impact on policing of budget cuts imposed by the home secretary.
Police Federation chairman Steve White is due to address the conference
In his keynote speech to the conference in Bournemouth, Police Federation Chairman Steve White is expected to describe neighbourhood policing as "just one of the endangered species in the new streamlined barren policing landscape".
He will say: "A generation of young people is growing up never seeing their local police unless they are unfortunate enough to experience a serious crime. Is that the type of remote, faceless police service the public deserves?"
Speaking to BBC Radio 4's Today programme, he said the Police Federation considered the results of its survey "deeply worrying".
He said: "What is happening is chief constables are having to make very, very difficult decisions. Do you put resources into policing 999 calls? Or do you put resources into neighbourhoods? It is really really challenging."
Responding to the federation's survey, Policing Minister Mike Penning said decisions on how neighbourhood policing teams were resourced and deployed were an operational matter for a force's chief constable, in association with its police and crime commissioner.
He said: "This flexible approach allows forces to respond to the individual needs and priorities of their local communities.
"The reduction in crime seen nationwide demonstrates there is no simple link between officer numbers and crime levels, the visibility of the police in the community and the quality of service provided."
He went on: "While we acknowledge that the police funding settlement is challenging there is no question that the police still have the resources to do their important work."
Theresa May will announce funding to stop people with mental health issues being detained in cells
In her conference address, Home Secretary Theresa May will announce government plans to bring an end to the practice of using police cells to detain people with mental health issues.
In 2014-15, about a fifth of the 21,995 people in England and Wales detained by police in a public place under section 136 of the Mental Health Act are said to have been held in a cell.
Mrs May will announce that up to £15m will be made available to the NHS to fund more "places of safety".
Ministers also plan to amend legislation to ensure that police cells are only used in future if a person can not be held safely elsewhere.
When she addressed the Police Federation conference a year ago, Mrs May said the way the Police Federation was structured, governed and financed needed to be reformed.
Federation members later agreed to implement all 36 recommendations made by an independent panel.