A union representing 6000 Auckland council workers says it wants a guarantee they will keep their jobs for at least 18 months.
The Government plans to merge the region's eight councils into one super-council and says it does not know how many jobs will be lost.
The Public Service Association says in similar cases overseas the vast majority of workers keep their jobs.
But national secretary Richard Wagstaff says that is cold comfort for workers who have had no assurances.
Mr Wagstaff says the PSA wants the guarantee to last at least through the transition to the new council at the end of 2010.