Buckinghamshire districts are due this month to debate a proposal to reorganise into two unitary councils, putting them on a collision course with Buckinghamshire CC.
The county council in September published plans for a single unitary, which it said could save £18m a year.
But the districts have countered with a proposal for one unitary covering Aylesbury Vale DC, which has long-cherished ambitions to go it alone, and another covering Chiltern, South Buckinghamshire and Wycombe DCs.
Aylesbury Vale leader Neil Blake (Con) said: “The four districts agree that the north and south are two separate economies and geographies with distinctive characteristics. We also believe that the relationships that need to be formed to serve the two communities are different.
“A single unitary will continue to have divided economic objectives and, as a result, will not be able to maximise the contribution this thriving economic area could make to the national economy.”
He said the single county unitary idea was “constrained by historic boundaries which do not reflect the communities which exist today, [and] will perpetuate the current failure to address rising costs in the delivery of social care and the failure to protect our children”.
Aylesbury Vale has a population of around 180,000 while the remaining three districts serve 335,000 residents.
Buckinghamshire leader Martin Tett (Con) said the districts had failed to produce a business case for their option.
In his New Year message to residents, he said: “We hope to hear a decision from government on our plans to modernise local government in Bucks early in the New Year.
“Sweeping away the existing, bureaucratic model of five different county and district councils in the area and replacing them with a single one delivering all services, will make things far simpler, cheaper and much more locally focused, with centres in towns and villages across the county for people to actually visit.”