Regional police forces have outlived their usefulness and should be replaced by a national force, a senior officers' group has said.
The Association of Chief Police Officers does not back a national force
The Police Superintendents Association believes the existing 43 police forces of England and Wales are based on outdated boundaries and structures.
The association makes the call in their official response to government plans for reform of the police service.
But the Association of Chief Police Officers does not favour such a move.
PSA president Rick Naylor said: "The existing structure of 43 autonomous entities aligned to boundaries which no longer reflect government structures in the regions, or the very local identities felt by individual communities has, we believe, outlived its usefulness."
"We have now reached the point where further significant improvement cannot be achieved without stepping outside the current structural arrangements.
"A logical solution would be a national police force deployed through a regional structure."
The association is the first of the three main police unions to back the controversial proposal.
"We recognise that the proposal to create a national police force does not appear to sit comfortably with the received wisdom that British policing is best provided by local units allied to traditional boundaries.
"It is, however, our firm view that our proposal would provide precisely such a structure at the most local level and would simultaneously provide the consistency of approach which is so glaringly absent at the present time."
He said there was a "clear gap" in the police's current ability to tackle crimes that spanned county borders.
Last November, Home Secretary David Blunkett hinted a possible restructure of policing in England and Wales could see smaller forces give way larger "strategic" forces.
But the Home Office's consultation paper, to which Mr Naylor was responding, stopped short of suggestion a national police force.
Acpo president Chris Fox said: "We see no benefit in a national police service.
"We must have a cohesive police service, able to deal with everything from the neighbourhood to the international.
"A national police service would be too remote and too complex."