Kent Police are to make a special case for remaining independent in any shake-up of national policing.
Michael Fuller said he would make a strong case for independence
Senior officers believe they outperform their urban counterparts, can "stand alone" on size and have a key role in policing the border with France.
Sweeping changes were recommended in a report which said the current structure of 43 forces should change.
Sussex Police said talks would be held in October. Surrey have so far backed reform and championed modernisation.
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.
At present 19 have fewer than 2,000 officers - Kent has 3,630.
Chief Constable Michael Fuller said he would be making a strong case for Kent "to remain a stand-alone independent police force".
He said Kent consistently performed better than big city forces.
"Our relationship with our colleagues in France is key to tackling security threats and immigration crime," he said.
"We believe that collaboration, rather than merger, will be the key to giving the public high-quality policing and value for money."
In Surrey, Chief Constable Bob Quick said: "Surrey strongly supports police reform and has championed the modernisation of the service.
"A review of force structures is timely and would complement other strands of police reform."
Sussex Police said: "Some reorganisation may indeed be necessary, but what form this takes should depend on local circumstances and take into account the views of local people.
"We are already working with our neighbours in Kent and Surrey, through the South East Policing Alliance, to develop shared services."
Kent Police Authority has launched a consultation. Sussex Police Authority will discuss its response on 20 October.