The favoured options for a major shake-up of police forces in the East were revealed in a Home Office report on Thursday.
Smaller forces face being merged into larger ones
The first option would see an eastern regional force. The second and third options would create two new forces.
The second option brings together Beds, Herts and Essex as one force, and Suffolk, Norfolk and Cambs, as another.
The third would merge Norfolk and Suffolk with Essex, and the Herts, Beds and Cambs police forces.
The report, which has been sent to police forces across the region, says these options would provide large enough police forces to deal with modern policing in the 21st Century.
A Home Office spokesman told BBC News on Thursday the three options are those considered best.
The report says proposals to allow Cambs, Essex and Bedfordshire to be a standalone police forces were "assessed as not suitable" because the forces the forces are not large enough.
A scheme to merge Bedfordshire with Thames Valley Police and proposals to merge Hertfordshire with Essex were also dismissed in the report.
A Home Office spokesman said these other options were not completely ruled out.
The news has been condemned by the Tory MP for Chelmsford West, Simon Burns, who believes Essex is big enough to have its own police force and to alter this would not improve law enforcement.
A spokeswoman for Essex Police said the stand-alone option was still on the table and senior figures were meeting next week to consider the matter.
Mike McFadyzean, of Cambridgeshire Police Federation, said: "The federation wants to see more detailed work on the options proposed to justify financially and resource-wise what would suit Cambridgeshire."