Sussex Police Authority members are being asked not to back plans to merge with another force.
Sussex Police said the force was not opposed to change
Chief Constable Ken Jones and the SPA chairman want to "halt the rush into structural reorganisation". The force had put forward five merger options.
A statement said council tax would rise to bring the force in line with its neighbours if a merger went ahead.
It also said the impossibility of reviewing merger options in 11 weeks had become clear to all involved.
The statement said: "While Sussex is not opposed to change, the impossibility of performing the task in less than three months has become clear to all those involved in the process.
"The first stage of the analysis resulted in a range of options.
"However, the next stage, to present business cases for the options, revealed the inadequacy of the methodology pursued by the Home Office."
A report will be put before Sussex Police Authority members at its meeting on 15 December.
In September, Kent Police said it would make a special case for remaining independent after sweeping changes were recommended in a report which said the current structure of 43 forces should change.
The report by Inspector of Constabulary Denis O'Connor, the former Surrey Chief Constable, said forces with more than 4,000 officers tended to perform best and called for smaller forces to merge.